Silence -Woverloaded-virtual warnings from generated code; NFC

GitOrigin-RevId: 65c22acfa4a412066e47c3171ff26fcbd62f970e
diff --git a/utils/TableGen/ClangAttrEmitter.cpp b/utils/TableGen/ClangAttrEmitter.cpp
index 0d8439b..6b76ad8 100644
--- a/utils/TableGen/ClangAttrEmitter.cpp
+++ b/utils/TableGen/ClangAttrEmitter.cpp
@@ -3672,6 +3672,11 @@
     }
   }
 
+  // If there are any decl or stmt attributes, silence -Woverloaded-virtual
+  // warnings for them both.
+  if (!DeclAttrs.empty() || !StmtAttrs.empty())
+    OS << "  using ParsedAttrInfo::diagMutualExclusion;\n\n";
+
   // If we discovered any decl or stmt attributes to test for, generate the
   // predicates for them now.
   if (!DeclAttrs.empty()) {