[llvm] [InstCombine] Revert the `signed icmp -> unsigned icmp` canonicalization when folding `icmp Pred min|max(X, Y), Z` (PR #76685)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM

https://github.com/llvm/llvm-project/pull/76685