[clang] [llvm] Fix KCFI types for generated functions with integer normalization (PR #104826)

[Sami Tolvanen via cfe-commits]

samitolvanen wrote:

> LG. It's best to have a test for the LLVM generated function, not just reuse kcfi-normalize.c whose module flags could be puzzling for readers.

I think we still need to test that Clang adds the module flag, but I added another test for the GCOV functions to make sure the hash is expected with and without integer normalization. PTAL.

https://github.com/llvm/llvm-project/pull/104826