[X86] Remove maximum vector length limit from combineBasicSADPattern.

createPSADBW uses SplitsOpsAndApply so should be able to handle
any size.

Restrict the extract result type to i32 or i64 since that's what
we have coverage for today and probably matches what the
isSimple() check gave us before.

Differential Revision: https://reviews.llvm.org/D76560