Mark pointer TStreamerElement as 'CannotSplit'
Mark pointer TStreamerElement as 'CannotSplit'

This prevents TBranchElement's GatherArtificialElements from
infinitely recursing (pointlessly) through a setup like:
   class Vertex;
   class Event {
     Vertex *fVertex;
   };
   class Vertex {
     Event *fEvent;
   };

root-mirror/root,olifre/root,olifre/root,karies/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,root-mirror/root,karies/root,karies/root,karies/root,root-mirror/root,olifre/root,root-mirror/root,olifre/root,karies/root,karies/root,olifre/root,root-mirror/root,karies/root,olifre/root,olifre/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,root-mirror/root,olifre/root,karies/root,karies/root