message: async_hover: fix callbacks as well
diff: @@ -44,16 +44,18 @@ int main(int argc, char *argv[])
  uint64_t uuid = uuids.at(0);
  unsigned magic = MAGIC_NUMBER;
  -
  - dl.device(uuid).action().arm_async({&receive_result, &magic});
  + dronelink::Action::CallbackData arm_receive = {&receive_result, &magic};
  + dl.device(uuid).action().arm_async(arm_receive);
  usleep(500000);
  - dl.device(uuid).action().takeoff_async({&receive_result, nullptr});
  + dronelink::Action::CallbackData takeoff_receive = {&receive_result, &magic};
  + dl.device(uuid).action().takeoff_async(takeoff_receive);
  usleep(5000000);
  - dl.device(uuid).action().land_async({&receive_result, nullptr});
  + dronelink::Action::CallbackData land_receive = {&receive_result, &magic};
  + dl.device(uuid).action().land_async(land_receive);
  return 0;
  }
  