media: i2c: og01a1b: Add management of optional sensor supply lines

Omnivision OG01A1B camera sensor is supplied by three power rails,
if supplies are present as device properties, include them into
sensor power up sequence.

Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>