GCS_MAVLink: schedule current waypoint rather than immediate send

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libraries/GCS_MAVLink/GCS_Common.cpp

@@ -517,7 +517,7 @@ void GCS_MAVLINK::handle_mission_set_current(AP_Mission &mission, const mavlink_
 
     // set current command
     if (mission.set_current_cmd(packet.seq)) {
-        mavlink_msg_mission_current_send(chan, packet.seq);
+        send_message(MSG_CURRENT_WAYPOINT);
     }
 }