various errors when invoking `dask.distributed.LocalCluster` with custom host (and port)

**What happened**:
Initiating `LocalCluster` after upadating dask to newest version reports errors.

codes that used to work:
```python
from dask import distributed as dis
clu = dis.LocalCluster(host='localhost:9000')
cli = dis.Client(dis)
```

**What you expected to happen**:
runs without error

**Minimal Complete Verifiable Example**:
case 1:
```python
clu = dis.LocalCluster(host='localhost:9000')
clu = dis.LocalCluster(host='localhost', port=9000)
```
reports "OSError: [Errno 98] Address already in use"

case 2:
```python
clu = dis.LocalCluster(host='localhost:9000', processes=False)
clu = dis.LocalCluster(host='localhost', port=9000, processes=False)
```
reports "ValueError: not enough values to unpack (expected 3, got 1)"

In case 2, I tried tracing back and found at least `dis.comm.addressing.addresses_from_user_args` parses my input correctly.

**Anything else we need to know?**:
This is a bug introduced since version 2021.10.0.
CLI tool `dask-scheduler --host localhost --port 9000` works fine with latest version.

**Environment**:

- Dask version: good before 2021.9.1, bad since 2021.10.0
- Python version: 3.7.12
- Operating System: CentOS 7
- Install method (conda, pip, source): miniconda+mamba

log of case 1:
```text
---------------------------------------------------------------------------
OSError Traceback (most recent call last)
/tmp/ipykernel_5274/1355496435.py in
----> 1 clu = dis.LocalCluster(host='localhost', port=9000)

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/local.py in __init__(self, name, n_workers, threads_per_worker, processes, loop, start, host, ip, scheduler_port, silence_logs, dashboard_address, worker_dashboard_address, diagnostics_port, services, worker_services, service_kwargs, asynchronous, security, protocol, blocked_handlers, interface, worker_class, scheduler_kwargs, scheduler_sync_interval, **worker_kwargs)
242 silence_logs=silence_logs,
243 security=security,
--> 244 scheduler_sync_interval=scheduler_sync_interval,
245 )
246

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/spec.py in __init__(self, workers, scheduler, worker, asynchronous, loop, security, silence_logs, name, shutdown_on_close, scheduler_sync_interval)
274 self._loop_runner.start()
275 self.sync(self._start)
--> 276 self.sync(self._correct_state)
277
278 async def _start(self):

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/cluster.py in sync(self, func, asynchronous, callback_timeout, *args, **kwargs)
256 return future
257 else:
--> 258 return sync(self.loop, func, *args, **kwargs)
259
260 def _log(self, log):

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/utils.py in sync(loop, func, callback_timeout, *args, **kwargs)
330 if error[0]:
331 typ, exc, tb = error[0]
--> 332 raise exc.with_traceback(tb)
333 else:
334 return result[0]

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/utils.py in f()
313 if callback_timeout is not None:
314 future = asyncio.wait_for(future, callback_timeout)
--> 315 result[0] = yield future
316 except Exception:
317 error[0] = sys.exc_info()

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/tornado/gen.py in run(self)
760
761 try:
--> 762 value = future.result()
763 except Exception:
764 exc_info = sys.exc_info()

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/spec.py in _correct_state_internal(self)
361 for w in workers:
362 w._cluster = weakref.ref(self)
--> 363 await w # for tornado gen.coroutine support
364 self.workers.update(dict(zip(to_open, workers)))
365

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/core.py in _()
281 )
282 else:
--> 283 await self.start()
284 self.status = Status.running
285 return self

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/nanny.py in start(self)
310 try:
311 await self.listen(
--> 312 start_address, **self.security.get_listen_args("worker")
313 )
314 except OSError as e:

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/core.py in listen(self, port_or_addr, allow_offload, **kwargs)
432 deserialize=self.deserialize,
433 allow_offload=allow_offload,
--> 434 **kwargs,
435 )
436 self.listeners.append(listener)

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/comm/core.py in _()
205 def __await__(self):
206 async def _():
--> 207 await self.start()
208 return self
209

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/comm/tcp.py in start(self)
476 # is large enough not to lose any.
477 sockets = netutil.bind_sockets(
--> 478 self.port, address=self.ip, backlog=backlog
479 )
480 except OSError as e:

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/tornado/netutil.py in bind_sockets(port, address, family, backlog, flags, reuse_port)
159 sock.setblocking(False)
160 try:
--> 161 sock.bind(sockaddr)
162 except OSError as e:
163 if (

OSError: [Errno 98] Address already in use
```

log of case 2:
```text
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
/tmp/ipykernel_5140/1306321815.py in
----> 1 clu = dis.LocalCluster(host='localhost:9000', processes=False)

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/local.py in __init__(self, name, n_workers, threads_per_worker, processes, loop, start, host, ip, scheduler_port, silence_logs, dashboard_address, worker_dashboard_address, diagnostics_port, services, worker_services, service_kwargs, asynchronous, security, protocol, blocked_handlers, interface, worker_class, scheduler_kwargs, scheduler_sync_interval, **worker_kwargs)
242 silence_logs=silence_logs,
243 security=security,
--> 244 scheduler_sync_interval=scheduler_sync_interval,
245 )
246

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/spec.py in __init__(self, workers, scheduler, worker, asynchronous, loop, security, silence_logs, name, shutdown_on_close, scheduler_sync_interval)
273 if not self.asynchronous:
274 self._loop_runner.start()
--> 275 self.sync(self._start)
276 self.sync(self._correct_state)
277

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/cluster.py in sync(self, func, asynchronous, callback_timeout, *args, **kwargs)
256 return future
257 else:
--> 258 return sync(self.loop, func, *args, **kwargs)
259
260 def _log(self, log):

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/utils.py in sync(loop, func, callback_timeout, *args, **kwargs)
330 if error[0]:
331 typ, exc, tb = error[0]
--> 332 raise exc.with_traceback(tb)
333 else:
334 return result[0]

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/utils.py in f()
313 if callback_timeout is not None:
314 future = asyncio.wait_for(future, callback_timeout)
--> 315 result[0] = yield future
316 except Exception:
317 error[0] = sys.exc_info()

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/tornado/gen.py in run(self)
760
761 try:
--> 762 value = future.result()
763 except Exception:
764 exc_info = sys.exc_info()

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/deploy/spec.py in _start(self)
302 cls = import_term(cls)
303 self.scheduler = cls(**self.scheduler_spec.get("options", {}))
--> 304 self.scheduler = await self.scheduler
305 self.scheduler_comm = rpc(
306 getattr(self.scheduler, "external_address", None) or self.scheduler.address,

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/core.py in _()
281 )
282 else:
--> 283 await self.start()
284 self.status = Status.running
285 return self

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/scheduler.py in start(self)
4058 **self.security.get_listen_args("scheduler"),
4059 )
-> 4060 self.ip = get_address_host(self.listen_address)
4061 listen_ip = self.ip
4062

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/comm/addressing.py in get_address_host(addr)
147 scheme, loc = parse_address(addr)
148 backend = registry.get_backend(scheme)
--> 149 return backend.get_address_host(loc)
150
151

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/comm/inproc.py in get_address_host(self, loc)
343
344 def get_address_host(self, loc):
--> 345 self.manager.validate_address(loc)
346 return self.manager.ip
347

~/miniconda3/envs/DataFlow/lib/python3.7/site-packages/distributed/comm/inproc.py in validate_address(self, addr)
66 Validate the address' IP and pid.
67 """
---> 68 ip, pid, suffix = addr.split("/")
69 if ip != self.ip or int(pid) != os.getpid():
70 raise ValueError(

ValueError: not enough values to unpack (expected 3, got 1)
```