[clang] [clang][CodeGen] Simplify code based on opaque pointers (PR #65624)

[Björn Pettersson via cfe-commits]

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@@ -51,14 +51,11 @@ struct CodeGenTypeCache {
     llvm::IntegerType *PtrDiffTy;
   };
 
-  /// void* in address space 0
+  /// void*, void** in address space 0
   union {
+    llvm::PointerType *UnqualPtrTy;
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bjope wrote:

Maybe `OpaquePtrTy` is a better name. But `Unqual` seem to be used in other places and I've typically used this instead of `PointerType::getUnqual`. But I'm not sure what `unqual` has been denoting originally (a pointer in address space zero?).

https://github.com/llvm/llvm-project/pull/65624