Update built-in USDT tools to support fully-specified probe API

> I do not particularly like BCC_USDT_HAS_FULLY_SPECIFIED_PROBE, but I guess we can live with it for now and later retire it with a few more releases. Otherwise, the patch looks good to me. In the future, we need to tweak python/C++ (esp. python) usdt user interfaces to include provider name.

As @yonghong-song indicates in https://github.com/iovisor/bcc/pull/2294#issuecomment-486018445, the current approach from #2294 relies on a compatibility hack.

We should phase this out and deprecate the old API as quickly as possible.

I have already got a PR in place for bpftrace to use he fully-specified API but this issue is to cover updating bcc tools and APIs:

Here are the references I found easily with grep:
* [ ] src/python/bcc/libbcc.py:221: `lib.bcc_usdt_enable_probe.restype = ct.c_int`
* [ ] src/python/bcc/libbcc.py:222: `lib.bcc_usdt_enable_probe.argtypes = [ct.c_void_p, ct.c_char_p, ct.c_char_p]`
* [ ] src/python/bcc/usdt.py:149: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] src/python/bcc/usdt.py:158: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] src/lua/bcc/usdt.lua:45: `assert(libbcc.bcc_usdt_enable_probe(
* [ ] src/lua/bcc/libbcc.lua:137: `int bcc_usdt_enable_probe(void *, const char *, const char *);`
* [ ] src/cc/bcc_usdt.h:72: `int bcc_usdt_enable_probe(void *, const char *, const char *);`
* [ ] src/cc/usdt/usdt.cc:449:`int bcc_usdt_enable_probe(void *usdt, const char *probe_name,`
* [ ] build/src/python/bcc-python/build/lib/bcc/libbcc.py:221: `lib.bcc_usdt_enable_probe.restype = ct.c_int`
* [ ] build/src/python/bcc-python/build/lib/bcc/libbcc.py:222: `lib.bcc_usdt_enable_probe.argtypes = [ct.c_void_p, ct.c_char_p, ct.c_char_p]`
* [ ] build/src/python/bcc-python/build/lib/bcc/usdt.py:149: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] build/src/python/bcc-python/build/lib/bcc/usdt.py:158: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] build/src/python/bcc-python/bcc/libbcc.py:221: `lib.bcc_usdt_enable_probe.restype = ct.c_int`
* [ ] build/src/python/bcc-python/bcc/libbcc.py:222: `lib.bcc_usdt_enable_probe.argtypes = [ct.c_void_p, ct.c_char_p, ct.c_char_p]`
* [ ] build/src/python/bcc-python/bcc/usdt.py:149: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] build/src/python/bcc-python/bcc/usdt.py:158: `if lib.bcc_usdt_enable_probe(self.context, probe.encode('ascii'),`
* [ ] build/src/lua/bcc.lua:2443: `int bcc_usdt_enable_probe(void *, const char *, const char *);`
* [ ] build/src/lua/bcc.lua:2968: `assert(libbcc.bcc_usdt_enable_probe(`

So it is the python and lua APIs are what need the most immediate attention here.

Once the built-in stuff has been ported over, I think we should deprecate the old API.

cc @yonghong-song

Start with the referenced Python files src/python/bcc/libbcc.py and src/python/bcc/usdt.py, then inspect the corresponding Lua bindings and C declarations in src/lua and src/cc. Trace bcc_usdt_enable_probe across these entry points and compare the built-in APIs with the fully specified probe API. Done means the Python and Lua APIs and built-in tools use the new API, with the old API ready for deprecation.

Written by the indexing model from the issue text.