[llvm] [PatternMatch] Add matchers for `m_{I,F,}Cmp` and `m_{I,F,}SpecificCmp`; NFC (PR #98282)

[Vitaly Buka via llvm-commits]

vitalybuka wrote:

Use after scope in the new test https://lab.llvm.org/buildbot/#/builders/169/builds/930

https://github.com/llvm/llvm-project/pull/98282