[X86] Remove unused node after morphing it from shr to and.

In some cases it won't get cleaned up properly leading to crashes
downstream. PR23353.

Based on a patch by Davide Italiano.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237828 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed