[media] v4l: videodev2: add buffer size to SDR format

Add buffer size field to struct v4l2_sdr_format. It is used for
negotiate streaming buffer size between application and driver.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

include/uapi/linux/videodev2.h

@@ -1783,10 +1783,12 @@ struct v4l2_pix_format_mplane {
 /**
  * struct v4l2_sdr_format - SDR format definition
  * @pixelformat:	little endian four character code (fourcc)
+ * @buffersize:		maximum size in bytes required for data
  */
 struct v4l2_sdr_format {
 	__u32				pixelformat;
-	__u8				reserved[28];
+	__u32				buffersize;
+	__u8				reserved[24];
 } __attribute__ ((packed));
 
 /**