[clang] [Clang] add emit -Wignored-base-class-qualifiers diagnostic for cv-qualified base classes (PR #132116)

[Aaron Ballman via cfe-commits]

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@@ -497,6 +497,7 @@ def GNUImaginaryConstant : DiagGroup<"gnu-imaginary-constant">;
 def IgnoredGCH : DiagGroup<"ignored-gch">;
 def IgnoredReferenceQualifiers : DiagGroup<"ignored-reference-qualifiers">;
 def IgnoredQualifiers : DiagGroup<"ignored-qualifiers", [IgnoredReferenceQualifiers]>;
+def IgnoredBaseClassQualifiers : DiagGroup<"ignored-base-class-qualifiers", [IgnoredReferenceQualifiers]>;
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AaronBallman wrote:

```suggestion
def IgnoredBaseClassQualifiers : DiagGroup<"ignored-base-class-qualifiers", [IgnoredQualifiers]>;
```
Right? This has nothing to do with reference qualifiers and the original group was `-Wignored-qualifiers`.

https://github.com/llvm/llvm-project/pull/132116