[clang] Thread Safety Analysis: Support warning on obtaining address of guarded variables (PR #123063)

[Nick Desaulniers via cfe-commits]

nickdesaulniers wrote:

Can any of the members in the structs be reorganized to put the mutex member declaration BEFORE the members they guard? Probably not always, but perhaps that's possible for most structures?

https://github.com/llvm/llvm-project/pull/123063