media: uapi: Add VP8 stateless decoder API

Add the parsed VP8 frame pixel format and controls, to be used
with the new stateless decoder API for VP8 to provide parameters
for accelerator (aka stateless) codecs.

Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Pawel Osciak <posciak@chromium.org>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>