Update PeachPy submodule (#78326)
Forked the repo, merged latest changes into pre-generated branch and
update pregenerared opcodes
Re-enabled NNPACK builds on MacOS
Picking https://github.com/Maratyszcza/PeachPy/commit/f8ef1a3c0a51a7691eb2b2a1bdd06335a03ff26f fixes https://github.com/pytorch/pytorch/issues/76094
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78326
Approved by: https://github.com/atalman, https://github.com/albanD
(cherry picked from commit fa7117c64a9cc740e71728701adb2cb2ccc143c4)
