adapt to new cadet API

src/multicast/gnunet-service-multicast.c

@@ -1330,7 +1330,6 @@ cadet_channel_create (struct Group *grp, struct GNUNET_PeerIdentity *peer)
 
   chn->channel = GNUNET_CADET_channel_create (cadet, chn, &chn->peer,
                                               &grp->cadet_port_hash,
-                                              GNUNET_CADET_OPTION_RELIABLE,
                                               cadet_notify_window_change,
                                               cadet_notify_disconnect,
                                               cadet_handlers);