[clang] [clang][CodeGen] Make `UnqualPtrTy` truly unqualified (PR #94388)

[Alexander Richardson via cfe-commits]

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@@ -51,9 +51,11 @@ struct CodeGenTypeCache {
     llvm::IntegerType *PtrDiffTy;
   };
 
+  /// unqualified void*
+  llvm::PointerType *UnqualPtrTy;
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arichardson wrote:

I'd argue we should just remove this variable, and the few cases that actually want AS0 can call PointerType::get(0) directly.

https://github.com/llvm/llvm-project/pull/94388