[TBAA] Only emit pointer tbaa metedata for record types. (#116991)
Be conservative if the type isn't a record type. Handling other types
may
require stripping const-qualifiers inside the type, e.g.
MemberPointerType.
Also look through array types same as through pointer types, to not
pessimize
arrays of pointers.
Without this, we assign different tags to the accesses for p an q in the
second test in cwg158.
PR: https://github.com/llvm/llvm-project/pull/116991