disable __torch_function__ overides for operators in torch.functional (#30839)
Summary:
For now I'm just removing the decorators from all of the currently overridable functions in `torch.functional`. This means they are no longer overridable, however this should fix the benchmark regressions reported in https://github.com/pytorch/pytorch/issues/30831. Moving forward we'll be looking at reducing the overhead of the python-level override mechanism and failing that, re-implementing all of these operators in C++.
cc hl475
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30839
Differential Revision: D18838848
Pulled By: ezyang
fbshipit-source-id: 22b8015d7b2f7a947f1ebc9632c998e081b48ad8
