[NFC][PowerPC] Add testcases for locking down the xxeval instruction support for ternary operators#141601

w2yehia merged 2 commits intollvm:mainllvm/llvm-project:mainfrom

tonykuttai:tvarghese/ternaryxxevaltonykuttai/llvm-project:tvarghese/ternaryxxevalCopy head branch name to clipboard