[media] v4l: uapi: add SDR format RU12LE

V4L2_SDR_FMT_RU12LE - Real unsigned 12-bit little endian sample
inside 16-bit (2 byte). V4L2 FourCC: RU12.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

include/uapi/linux/videodev2.h

@@ -453,6 +453,7 @@ struct v4l2_pix_format {
 /* SDR formats - used only for Software Defined Radio devices */
 #define V4L2_SDR_FMT_CU8          v4l2_fourcc('C', 'U', '0', '8') /* IQ u8 */
 #define V4L2_SDR_FMT_CU16LE       v4l2_fourcc('C', 'U', '1', '6') /* IQ u16le */
+#define V4L2_SDR_FMT_RU12LE       v4l2_fourcc('R', 'U', '1', '2') /* real u12le */
 
 /* priv field value to indicates that subsequent fields are valid. */
 #define V4L2_PIX_FMT_PRIV_MAGIC		0xfeedcafe