message: mission_impl: fix types unknown for Windows build
diff: @@ -255,7 +255,7 @@ void MissionImpl::assemble_mavlink_messages()
  // The speed has changed, we need to add a speed command.
  // Current is the 0th waypoint
  - u_int8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  + uint8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  uint8_t autocontinue = 1;
  @@ -293,7 +293,7 @@ void MissionImpl::assemble_mavlink_messages()
  // The gimbal has changed, we need to add a gimbal command.
  // Current is the 0th waypoint
  - u_int8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  + uint8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  uint8_t autocontinue = 1;
  @@ -329,7 +329,7 @@ void MissionImpl::assemble_mavlink_messages()
  // There is a camera action that we need to send.
  // Current is the 0th waypoint
  - u_int8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  + uint8_t current = ((_mavlink_mission_item_messages.size() == 0) ? 1 : 0);
  uint8_t autocontinue = 1;
  