media: atomisp-ov2680: Improve ov2680_set_fmt() error handling

Exit with an error on any i2c-write errors, rather then only
exiting with an error when ov2680_get_intg_factor() fails.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>