Revert "[X86] combineCMP - attempt to simplify KSHIFTR mask element...

Revert "[X86] combineCMP - attempt to simplify KSHIFTR mask element extractions when just comparing against zero"

This reverts commit 239ab16e.

This causes crashes when compiling chromium with asan, attached reduced ir at: https://reviews.llvm.org/rG239ab16ec1213749a2228368298519b377d336bb#124559