Remove PyCFunction casts as much as possible. (#46227)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46227
Follow up from https://github.com/pytorch/pytorch/issues/45419, in
this PR I've removed as many PyCFunction casts as I could from the codebase.
The only ones I didn't remove were the ones with `METH_VARARGS | METH_KEYWORDS`
which have 3 parameters instead of 2 and had to be casted. Example: `
{"copy_", (PyCFunction)(void(*)(void))THPStorage_(copy_), METH_VARARGS |
METH_KEYWORDS, nullptr},`
ghstack-source-id: 114632704
Test Plan: waitforbuildbot
Reviewed By: albanD
Differential Revision: D24269435
fbshipit-source-id: 025cfd43a9a2a3e59f6b2951c1a78749193d77cf
