[llvm] [NFC][PPC] Class XXEvalPattern : name change and type agnostic design (PR #143675)

[Tony Varghese via llvm-commits]

tonykuttai wrote:

@lei137 @amy-kwan 

This PR is created to resolve this comment: https://github.com/llvm/llvm-project/pull/141733#discussion_r2132602483

Thanks

https://github.com/llvm/llvm-project/pull/143675