V4L/DVB: mx2_camera: fix for list bufnum in frame_done_emma

The emma uses bufnum 1 and 0. This patch tells the bufqueue to change
the next buffer to the next one and not the current one.
Otherwise the BUG_ON above will trigger everytime.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/mx2_camera.c

@@ -1201,7 +1201,7 @@ static void mx27_camera_frame_done_emma(struct mx2_camera_dev *pcdev,
 	buf = list_entry(pcdev->capture.next,
 			struct mx2_buffer, vb.queue);
 
-	buf->bufnum = bufnum;
+	buf->bufnum = !bufnum;
 
 	list_move_tail(pcdev->capture.next, &pcdev->active_bufs);