Add 'override' specifier to overridden destructor methods

Test: Build
Bug: 37752547
Change-Id: I157e1c2aa5d9d08fcab6055a3ca48c6ed8a050fc
diff --git a/include/gui/BufferQueue.h b/include/gui/BufferQueue.h
index 266f0aa..d532e2a 100644
--- a/include/gui/BufferQueue.h
+++ b/include/gui/BufferQueue.h
@@ -61,7 +61,7 @@
     class ProxyConsumerListener : public BnConsumerListener {
     public:
         explicit ProxyConsumerListener(const wp<ConsumerListener>& consumerListener);
-        virtual ~ProxyConsumerListener();
+        ~ProxyConsumerListener() override;
         virtual void onFrameAvailable(const BufferItem& item) override;
         virtual void onFrameReplaced(const BufferItem& item) override;
         virtual void onBuffersReleased() override;