Fix for PR4225: When rewriter reuse a value in a physical register , it clear the...

Fix for PR4225: When rewriter reuse a value in a physical register , it clear the register kill operand marker and its kill ops information. However, the cleared operand may be a def of a super-register. Clear the kill ops info for the super-register's sub-registers as well.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72758 91177308-0d34-0410-b5e6-96231b3b80d8