[PowerPC] Make sure that we remove dead PHI nodes after the PPCCTRLoops pass.

Commiting on behalf of Stefan Pintilie.
Differential Revision: https://reviews.llvm.org/D34829

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307180 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed