[llvm] Normalize file path to fix problems with different folder separators. (PR #215225)

[via llvm-commits]

VladimirMedic wrote:

> > Inconsistent file path separators in isa disassembly for line correlation
> 
> Could you give an example of this, please?
For example, we see this in the output. It probably comes from the separator that was used in #include
; C:\Program Files\AMD\ROCm\7.1\include\hip/amd_detail\amd_hip_runtime.h:259

> Do any of the tests still cover the input path being a mix of separators on Windows? I want to make sure we don't lose this coverage by accident in the process of improving the functionality.

Yes, but the tests were not checking it correctly due to the lines that were accepting both separators. It will be fixed in the next commit.

https://github.com/llvm/llvm-project/pull/215225