[llvm] [mlir] Add llvm::min/max_element and use it in llvm/ and mlir/ directories. (PR #84678)

[Jakub Kuderski via llvm-commits]

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

Usually I prefer separating STLExtras changes from updating the codebase to make things easier to revert, but this looks simple enough to do in one step IMO

https://github.com/llvm/llvm-project/pull/84678