Fix a crash on iOS due to memory alignment since making mNextHandle atomic.
Fix a crash on iOS due to memory alignment since making mNextHandle atomic.

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