ARM: add correct kill flags when combining stm instructions

When the store sequence being combined actually stores the base register, we
should not mark it as killed until the end.

rdar://21504262

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@241003 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed