Fix -Winconsistent-missing-override in CodeGenAction.cpp

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@288227 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CodeGenAction.cpp

@@ -152,7 +152,7 @@ namespace clang {
         LLVMIRGeneration.stopTimer();
     }
 
-    void HandleInterestingDecl(DeclGroupRef D) {
+    void HandleInterestingDecl(DeclGroupRef D) override {
       // Ignore interesting decls from the AST reader after IRGen is finished.
       if (!IRGenFinished)
         HandleTopLevelDecl(D);