media: uapi: h264: Further clarify scaling lists order

Commit 0b0393d59e ("media: uapi: h264: clarify
expected scaling_list_4x4/8x8 order") improved the
documentation on H264 scaling lists order.

This commit improves the documentation by clarifying
that the lists themselves are expected in raster scan order.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst

@@ -1725,12 +1725,14 @@ enum v4l2_mpeg_video_h264_hierarchical_coding_type -
       - ``scaling_list_4x4[6][16]``
       - Scaling matrix after applying the inverse scanning process.
         Expected list order is Intra Y, Intra Cb, Intra Cr, Inter Y,
-        Inter Cb, Inter Cr.
+        Inter Cb, Inter Cr. The values on each scaling list are
+        expected in raster scan order.
     * - __u8
       - ``scaling_list_8x8[6][64]``
       - Scaling matrix after applying the inverse scanning process.
         Expected list order is Intra Y, Inter Y, Intra Cb, Inter Cb,
-        Intra Cr, Inter Cr.
+        Intra Cr, Inter Cr. The values on each scaling list are
+        expected in raster scan order.
 
 ``V4L2_CID_MPEG_VIDEO_H264_SLICE_PARAMS (struct)``
     Specifies the slice parameters (as extracted from the bitstream)