[llvm] [X86] Handle shifts + and in `LowerSELECTWithCmpZero` (PR #107910)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

Thanks @goldsteinn - I'm trying to find profitable uses for these folds on CMOV targets - any ideas?

https://github.com/llvm/llvm-project/pull/107910