[clang] [llvm] [Coverage] Emit skipped regions in mappings of unused functions (PR #232831)

[Fabian Meumertzheim via cfe-commits]

fmeum wrote:

This should be merged after https://github.com/llvm/llvm-project/pull/233136 and https://github.com/llvm/llvm-project/pull/233137.

https://github.com/llvm/llvm-project/pull/232831