Automatically add types to Python modules

PR python/32163 points out that various types provided by gdb are not
added to the gdb module, so they aren't available for interactive
inspection.  I think this is just an oversight.

This patch fixes the problem by introducing a new helper function that
both readies the type and then adds it to the appropriate module.  The
patch also poisons PyType_Ready, the idea being to avoid this bug in
the future.

v2:
* Fixed a bug in original patch in gdb.Architecture registration
* Added regression test for the types mentioned in the bug

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32163
Reviewed-By: Alexandra Petlanova Hajkova <ahajkova@redhat.com>

gdb/python/python.c

@@ -2316,7 +2316,7 @@ init_done:
     return false;
 
 #define GDB_PY_DEFINE_EVENT_TYPE(name, py_name, doc, base)	\
-  if (gdbpy_initialize_event_generic (&name##_event_object_type, py_name) < 0) \
+  if (gdbpy_type_ready (&name##_event_object_type) < 0) \
     return false;
 #include "py-event-types.def"
 #undef GDB_PY_DEFINE_EVENT_TYPE