[lldb] Allow flexible importing of in_call_stack

[kastiglione]

Summary

Allow in_call_stack to be imported in either of the following ways:

command script import path/to/in_call_stack.py
command script import lldb.utils.in_call_stack

rdar://102249295

[jingham]

I made this change in situ in the version we ship in the LLDB.framework, and this does the right thing! Thanks!

lldb/examples/python/in_call_stack.py

 #!/usr/bin/env python
 
 
 def __lldb_init_module(debugger, internal_dict):
   debugger.HandleCommand(
-      'command alias in_call_stack breakpoint command add --python-function in_call_stack.in_call_stack -k name -v %1'
+      f'command alias in_call_stack breakpoint command add --python-function {__name__}.in_call_stack -k name -v %1'
   )
 
 
 def in_call_stack(frame, bp_loc, arg_dict, _):
   """Only break if the given name is in the current call stack."""
   name = arg_dict.GetValueForKey('name').GetStringValue(1000)
   thread = frame.GetThread()
   found = False