[llvm] [LLVM-Reduce] - Distinct Metadata Reduction (PR #96072)

[Michal Paszkowski via llvm-commits]

https://github.com/michalpaszkowski requested changes to this pull request.

Hi @rbintel! Thank you for the pull request. I added some initial comments on the style below. 

https://github.com/llvm/llvm-project/pull/96072