[clang] [Clang] [Sema] No longer diagnose type definitions in `offsetof` in C23 mode (PR #84169)

[Shafik Yaghmour via cfe-commits]

https://github.com/shafik commented:

Should we verify that we diagnose the case where the definition includes a comma?

https://github.com/llvm/llvm-project/pull/84169