Revert "LivePhysRegs: Fix addLiveOutsNoPristines() for return blocks past PEI"

Tentatively revert this to see if it fixes the buildbot stage2
breakages.

This reverts commit r303938.
This reverts commit r303954.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303960 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed