(hironx_ros_bridge) add missing run_depend package.

`openni2_launch` is [needed in a launch file](https://github.com/start-jsk/rtmros_hironx/blob/6e3b52aa92bb163751e4f07b3c281c84019fa993/hironx_ros_bridge/launch/hironx_kinect.launch#L10).