Add some compiler flags for building cpp extensions on Windows (#23472)
Summary:
(1) Add `COMMON_MSVC_FLAGS` to the flags in the ninja codepath
(2) Add `/EHsc` to `COMMON_MSVC_FLAG`
(3) Remove `-fPIC` and `-std=c++11` from the flags in the windows codepath
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23472
Differential Revision: D16532993
Pulled By: soumith
fbshipit-source-id: bc2d983f5f8b4eae9c7385bf170f155679e92e87