Terrain: Fix memory leak after updating lightmaps
Terrain: Fix memory leak after updating lightmaps

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