V4L/DVB: v4l: add V4L2_PIX_FMT_Y4 and V4L2_PIX_FMT_Y6 pixelformats

Old 4 and 6 bit greyscale pixel formats for the old bw-qcam webcam.
This is needed to convert it to V4L2.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h
index 418dacf..6fb0b2d 100644
--- a/include/linux/videodev2.h
+++ b/include/linux/videodev2.h
@@ -294,6 +294,8 @@
 
 /* Grey formats */
 #define V4L2_PIX_FMT_GREY    v4l2_fourcc('G', 'R', 'E', 'Y') /*  8  Greyscale     */
+#define V4L2_PIX_FMT_Y4      v4l2_fourcc('Y', '0', '4', ' ') /*  4  Greyscale     */
+#define V4L2_PIX_FMT_Y6      v4l2_fourcc('Y', '0', '6', ' ') /*  6  Greyscale     */
 #define V4L2_PIX_FMT_Y10     v4l2_fourcc('Y', '1', '0', ' ') /* 10  Greyscale     */
 #define V4L2_PIX_FMT_Y16     v4l2_fourcc('Y', '1', '6', ' ') /* 16  Greyscale     */