Add support for the .get_selection() pad operation to the ov5670 sensor
driver.

Report the native sensor size (pixel array), the crop bounds (readable
pixel array area) and the current and default analog crop rectangles.

Currently all driver's modes use an analog crop rectangle of size
[12, 4, 2600, 1952]. Instead of hardcoding the value in the operation
implementation, ad an .analog_crop field to the sensor's modes
definitions, to make sure that if any mode gets added, its crop
rectangle will be defined as well.

While at it re-sort the modes' field definition order to match the
declaration order and initialize the crop rectangle in init_cfg().

[Sakari Ailus: Fix a typo on comments (03800 -> 0x3800)]
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Luca Weiss <luca@z3ntu.xyz>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>