media: cedrus: h265: Support decoding 10-bit frames

10-bit frames needs extra buffer space when 8-bit capture format is
used. Use previously prepared infrastructure to adjust buffer size.

Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>