[X86][SSE] combineSetCCMOVMSK - allow comparison with upper (known zero) bits...

[X86][SSE] combineSetCCMOVMSK - allow comparison with upper (known zero) bits in MOVMSK(SHUFFLE(X,u)) -> MOVMSK(X) fold

Extension to rG74f98391, we can also include any of the upper (known zero) bits in the comparison in the shuffle removal fold, just as long as we demand all the elements of the movmsk source vector.