[clang][Sema] Fix uninitialized `SourceLocation` for types with multiple attributes and macros.

Some `TypeLoc`s are considered "sugar" and we go past them in
`GetTypeSourceInfoForDeclarator`. The problem is that we peel off only
the same kind of `TypeLoc` at the time which makes it impossible to
handle mixed sequences like
`AttributedTypeLoc - MacroQualifiedTypeLoc - AttributedTypeLoc - PointerTypeLoc`

In this situation, as shown in the added test, we don't get to
`PointerTypeLoc` and don't set its starLoc leaving it uninitialized.

Address FIXME and peel off "sugar" `TypeLoc`s regardless of their order.

rdar://102149264

Differential Revision: https://reviews.llvm.org/D141424