[clang] [clang][MSExtentions] Fix invalid overload failure about the loss of `__unaligned` qualifier (PR #65248)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman approved this pull request.

LGTM; I think this can be held out of 17.0.0 but would be fine to backport to a later 17.x release if desired.

https://github.com/llvm/llvm-project/pull/65248