[clang] [clang][NFC] Adjust TBAA Base Info API (PR #73263)

[Nathan Sidwell via cfe-commits]

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@@ -95,8 +95,6 @@ static bool TypeHasMayAlias(QualType QTy) {
 
 /// Check if the given type is a valid base type to be used in access tags.
 static bool isValidBaseType(QualType QTy) {
-  if (QTy->isReferenceType())
-    return false;
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urnathan wrote:

would you prefer I separate this piece out to a separate PR?

https://github.com/llvm/llvm-project/pull/73263