media: coda: move register debugging to coda_debug level 3

This allows to use coda_debug level 2 for verbose but not quite as
verbose debug logging. Register access level logging is of limited
use anyway, as this includes busy polling of status bits.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>