[llvm] [X86] Fix CCMP miscompile for flag-source-folded SETCC leaves (PR #217682)

[Evgenii Kudriashov via llvm-commits]

e-kud wrote:

I created two commits on the branch to show which CG was broken. I'll commit them separately. Once PR is approved.

https://github.com/llvm/llvm-project/pull/217682