[clang] [Clang] Fix Microsoft ABI inheritance model when member pointer is used in a base specifier (PR #91990)

[Max Winkler via cfe-commits]

MaxEW707 wrote:

@rnk @zmodem Sorry for the ping. Its been a bit since this got reviewed and I recently hit this ABI case when moving some parts of a larger project to clang.

https://github.com/llvm/llvm-project/pull/91990