[clang] Add support for MS inp functions. (PR #93804)

[Malay Sanghi via cfe-commits]

MalaySanghi wrote:

This could probably have been a part of https://github.com/llvm/llvm-project/pull/93774 . If that's preferred, I'll add this change as a new commit to that PR.

https://github.com/llvm/llvm-project/pull/93804