[analyzer] Correctly marked a virtual function 'override'

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@340280 91177308-0d34-0410-b5e6-96231b3b80d8

lib/StaticAnalyzer/Checkers/UninitializedObject/UninitializedObjectChecker.cpp

@@ -117,7 +117,7 @@ public:
 
   virtual void printSeparator(llvm::raw_ostream &Out) const override {}
 
-  virtual bool isBase() const { return true; }
+  virtual bool isBase() const override { return true; }
 };
 
 } // end of anonymous namespace