[Samples] Fixed crash in CubeMapping sample on Stop sample attempt
[Samples] Fixed crash in CubeMapping sample on Stop sample attempt

paroj/ogre,OGRECave/ogre,paroj/ogre,RealityFactory/ogre,RealityFactory/ogre,OGRECave/ogre,paroj/ogre,OGRECave/ogre,paroj/ogre,OGRECave/ogre,OGRECave/ogre,RealityFactory/ogre,RealityFactory/ogre,RealityFactory/ogre,paroj/ogre