[clang] [Clang][Sema] Diagnose type mismatch on redeclaration after redefinition error (PR #228212)

[Shafik Yaghmour via cfe-commits]

https://github.com/shafik commented:

FYI, the related issue is fixed by this, so it should just be listed in the Fixes: list. 

You don't need to say added `clang/test/Sema/redefinition-then-different-type.c` b/c we can see that in the change list and we will assume you tested it b/c that is required. The CI will fail if it does not work.

https://github.com/llvm/llvm-project/pull/228212