Make sure that tp_free frees the int the same way as tp_dealloc would.
This fixes the problem that Barry reported on python-dev:
>>> 23000 .__class__ = bool
crashes in the deallocator. This was because int inherited tp_free
from object, which uses the default allocator.
2.2. Bugfix candidate.
(trivial change in backport: "freefunc" -> "destructor")
Original patch(es):
python/dist/src/Objects/intobject.c:2.82