llvm/lib/MC/MCParser/AsmParser.cpp: [ms-inline-asm] Fix a couple of undefined behaviors. Operand->needAddressOf() is not initialized at !Operand->isReg().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172153 91177308-0d34-0410-b5e6-96231b3b80d8