fix mesh leak in camera class

src/camera.h

@@ -173,6 +173,9 @@ private:
 	// If 0, left-click digging animation
 	// If 1, right-click digging animation
 	s32 m_digging_button;
+
+	//dummymesh for camera
+	irr::scene::IAnimatedMesh* m_dummymesh;
 };
 
 #endif