media: i2c: ov01a10: Replace exposure->min/step with direct define use

media: i2c: ov01a10: Replace exposure->min/step with direct define use

The exposure minimum and step are constant use the defines for this
instead of retrieving these from the exposure-control.

Signed-off-by: Hans de Goede <hansg@kernel.org>
Tested-by: Mehdi Djait <mehdi.djait@linux.intel.com> # Dell XPS 9315
Reviewed-by: Mehdi Djait <mehdi.djait@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>