bpo-37151: remove special case for PyCFunction from PyObject_Call (GH-14684)

bpo-37151: remove special case for PyCFunction from PyObject_Call

Alse, make the undocumented function PyCFunction_Call an alias
of PyObject_Call and deprecate it.
diff --git a/Tools/gdb/libpython.py b/Tools/gdb/libpython.py
index e40f79b..e28513d 100755
--- a/Tools/gdb/libpython.py
+++ b/Tools/gdb/libpython.py
@@ -1564,7 +1564,7 @@
             return False
 
         if (caller.startswith('cfunction_vectorcall_') or
-            caller == 'cfunction_call_varargs'):
+            caller == 'cfunction_call'):
             arg_name = 'func'
             # Within that frame:
             #   "func" is the local containing the PyObject* of the