drm/dp_mst: Remove bogus conditional in drm_dp_update_payload_part1()

There's no reason we need this, it's just confusing looking.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Juston Li <juston.li@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20181214012604.13746-2-lyude@redhat.com

drivers/gpu/drm/drm_dp_mst_topology.c

@@ -1896,9 +1896,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
 			req_payload.num_slots = 0;
 		}
 
-		if (mgr->payloads[i].start_slot != req_payload.start_slot) {
-			mgr->payloads[i].start_slot = req_payload.start_slot;
-		}
+		mgr->payloads[i].start_slot = req_payload.start_slot;
 		/* work out what is required to happen with this payload */
 		if (mgr->payloads[i].num_slots != req_payload.num_slots) {