message: telemetry: only listen to autopilot for armed flag
  If we listen to the heartbeats from all components the armed flag will
  flicker. Therefore let's filter by component ID.
diff: @@ -491,6 +491,10 @@ void TelemetryImpl::process_sys_status(const mavlink_message_t &message)
  void TelemetryImpl::process_heartbeat(const mavlink_message_t &message)
  {
  + if (message.compid != MAV_COMP_ID_AUTOPILOT1) {
  + return;
  + }
  +
  mavlink_heartbeat_t heartbeat;
  mavlink_msg_heartbeat_decode(&message, &heartbeat);
  