media: i2c: imx290: Properly encode registers as little-endian

The conversion to CCI also converted the multi-byte register access to
big-endian. Correct the register definition by using the correct
little-endian ones.

Fixes: af73323b ("media: imx290: Convert to new CCI register access helpers")
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
[Sakari Ailus: Fixed the Fixes: tag.]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>