[llvm] [Instcombine]: `llvm.ucmp` and `llvm.scmp` recognition (PR #168505)

[via llvm-commits]

kper wrote:

@dtcxzyw thanks, I fixed two bugs. First, the return type of the intrinsic wasn't correct. Second, the fold must not be applied to pointer comparisons.
Would you please rerun the benchmark? Thank you!

https://github.com/llvm/llvm-project/pull/168505