MLK-20756: mxc-jpeg: gst-launch does not exit after displaying jpeg image with jpeg-dec

Add notify_eos function to enqueue V4L2_EVENT_EOS for the application.
Call notify_eos after V4L2_DEC_CMD_STOP was received,
or, if there still are source buffers to process, later in dqbuf.
Add mxc_jpeg_dqbuf and send V4L2_EVENT_EOS if needed.

Fix for "Driver should never set v4l2_buffer.field to ANY" warning in
gst-launch, by setting V4L2_FIELD_NONE in mxc_jpeg_dqbuf.

Tested with gst-launch and v4l2video0jpegdec plugin:
gst-launch-1.0 filesrc location=<image.jpg> ! jpegparse ! v4l2video5jpegdec
        ! waylandsink

Signed-off-by: Mirela Rabulea <mirela.rabulea@nxp.com>