USDT probes with arguments can't be attached to the same BPF C function

uprobes don't seem to have this limitation. Is this a USDT bug or is this behaviour by design?

Consider a C/C++ application with these USDT probes:
```
DTRACE_PROBE(test, probe_noarg_0);
DTRACE_PROBE(test, probe_noarg_1);
DTRACE_PROBE1(test, probe_arg_0, "myarg0");
DTRACE_PROBE1(test, probe_arg_1, "myarg1");
```

Attaching the same BPF C function probe_func to two distinct USDT probes that have no arguments works:
```
u.enable_probe(probe="probe_noarg_0", fn_name="probe_func")
u.enable_probe(probe="probe_noarg_1", fn_name="probe_func")
```

However, attaching the same BPF C function probe_func to two distinct USDT probes **that have an argument** errors out with `/virtual/main.c:7:28: error: redefinition of '_bpf_readarg_probe_func_1'`.
```
u.enable_probe(probe="probe_arg_0", fn_name="probe_func")
u.enable_probe(probe="probe_arg_1", fn_name="probe_func")
```

Reproduce the issue with the C/C++ USDT probes and the two u.enable_probe calls shown in the report. Inspect the generated /virtual/main.c around line 7, where _bpf_readarg_probe_func_1 is redefined. Done means determining whether this is intended behavior or allowing the shared function to attach to both argument-bearing probes without that redefinition error.

Written by the indexing model from the issue text.