Fix for exodus-disabled builds.
Fix for exodus-disabled builds.

Refs #3225

dschwen/libmesh,libMesh/libmesh,libMesh/libmesh,libMesh/libmesh,libMesh/libmesh,dschwen/libmesh,libMesh/libmesh,libMesh/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,dschwen/libmesh,jwpeterson/libmesh,dschwen/libmesh,libMesh/libmesh,dschwen/libmesh,dschwen/libmesh,dschwen/libmesh,dschwen/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,libMesh/libmesh,jwpeterson/libmesh