STYLE: Update doxygen comment of vtkMRMLScene::AddReferencedNodeID

The comment document the changes introduced by commit r22669

From: Andras Lasso <lasso@queensu.ca>

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22790 3bd1e089-480b-0410-8dfb-8563597acbee