Allow edit of ipakrbokasdelegate in Web UI when attrlevelrights are unknown
    
    Old host entries are missing object class with krbticketflags attribute. Therefore UI does not receive attrlevelrights for it. This OC is added when ipakrbokasdelegate is set.
    
    This patch adds the usual hack for such cases.
    
    https://fedorahosted.org/freeipa/ticket/3940