Zap the last two -Wself-assign warnings in llvm.

Simplify RALinScan::DowngradeRegister with TRI::getOverlaps while we are there.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122940 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed