When determining whether two types are reference-compatible, check

non-CVR qualifiers as well as CVR qualifiers. For example, don't allow
a reference to an integer in address space 1 to bind to an integer in
address space 2.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130411 91177308-0d34-0410-b5e6-96231b3b80d8