Remove unused atomics detection code. (#23089)
Summary:
USE_{C11,MSC,GCC}_ATOMICS are not used in PyTorch or submodules. Now we remove their underlying detection code.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23089
Differential Revision: D16402750
Pulled By: ezyang
fbshipit-source-id: fde84b958eb0b5b4d3f0406acefa92ab30ea43be
