[X86] Don't create SHRUNKBLEND when the condition is used by the true or false operand of the vselect.

Fixes PR34592.

Differential Revision: https://reviews.llvm.org/D42628

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@323672 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed