media: uapi: videodev2: Add support for AV1 stateful decoder

media: uapi: videodev2: Add support for AV1 stateful decoder

Introduce a new pixel format, V4L2_PIX_FMT_AV1, to the
Video4Linux2(V4L2) API. This format is intended for AV1
bitstreams in stateful decoding/encoding workflows.
The fourcc code 'AV10' is used to distinguish
this format from the existing V4L2_PIX_FMT_AV1_FRAME,
which is used for stateless AV1 decoder implementation.

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Hans Verkuil <hverkuil+cisco@kernel.org>
Signed-off-by: Deepa Guthyappa Madivalara <deepa.madivalara@oss.qualcomm.com>
Tested-by: Val Packett <val@packett.cool>
Signed-off-by: Bryan O'Donoghue <bod@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>