drm/dp_mst: Get rid of list clear in destroy_connector_work

This seems to be some leftover detritus from before the port/mstb kref
cleanup and doesn't do anything anymore, so get rid of it.

Cc: Juston Li <juston.li@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <hwentlan@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190903204645.25487-3-lyude@redhat.com

drivers/gpu/drm/drm_dp_mst_topology.c

@@ -3760,8 +3760,6 @@ static void drm_dp_destroy_connector_work(struct work_struct *work)
 		list_del(&port->next);
 		mutex_unlock(&mgr->destroy_connector_lock);
 
-		INIT_LIST_HEAD(&port->next);
-
 		mgr->cbs->destroy_connector(mgr, port->connector);
 
 		drm_dp_port_teardown_pdt(port, port->pdt);