[llvm] [X86] SimplifyDemandedBitsForTargetNode - PCMPGT(0,X) only demands the signbit of X (PR #163981)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

```
Failed Tests (1):
LLVM :: Other/pass-pipeline-parsing.ll
```
@boomanaiden154 Any idea why the CI has started to always fail here?

https://github.com/llvm/llvm-project/pull/163981