[llvm] [clang][OpenMP] Fix bug #62099 - use hash value when inode ID cannot be determined (PR #131646)

[Michael Kruse via llvm-commits]

Meinersbur wrote:

> Is there reason you do not want to normalize the filename for hashing?

I am still curious. You will get different IDs for `somedir/../file.cpp` and `file.cpp`.

https://github.com/llvm/llvm-project/pull/131646