These values will be used by various drivers implementing the VP8
stateless API.

This had been suggested by Ezequiel Garcia for the Cedrus VP8 driver.
Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>