Fix comment typo.

No functionality changed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@212462 91177308-0d34-0410-b5e6-96231b3b80d8
MS ABI: Don't unnecessarily use CGM abstraction

If we are in MicrosoftCXXABI, we don't need to use CGM to get a
TypeDescriptor.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@212463 91177308-0d34-0410-b5e6-96231b3b80d8