[X86] Add a one use check to the setcc inversion code in combineVSelectWithAllOnesOrZeros

If we're going to generate a new inverted setcc, we should make sure we will be able to remove the old setcc.

Differential Revision: https://reviews.llvm.org/D56765

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351378 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed