media: dt-bindings: media: cedrus: Add H6 compatible

This adds a compatible for H6. H6 VPU supports 10-bit HEVC decoding and
additional AFBC output format for HEVC.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>