[lldb/crashlog] Remove dead code (NFC)

This patch cleans up the crashlog.py script and removes dead code.

Signed-off-by: Med Ismail Bennani <[email protected]>

Author: medismailben

lldb/examples/python/crashlog.py

@@ -1228,11 +1228,6 @@ def parse_instructions(self, line):
         pass
 
 
-def usage():
-    print("Usage: lldb-symbolicate.py [-n name] executable-image")
-    sys.exit(0)
-
-
 def save_crashlog(debugger, command, exe_ctx, result, dict):
     usage = "save_crashlog [options] <output-path>"
     description = """Export the state of current target into a crashlog file"""