media: atomisp-ov2680: Remove a bunch of unused vars from ov2680_device

Remove a couple of variables which where either completely unused,
or only ever got a value assigned to them but were never read.

Link: https://lore.kernel.org/linux-media/20211107171549.267583-2-hdegoede@redhat.com


Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>