media: mt9p031: Implement crop bounds get selection

Implement V4L2_SEL_TGT_CROP_BOUNDS query in get_selection subdev op
for this sensor. This is required e.g. to bind it to STM32MP15x DCMI.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Stefan Riedmueller <s.riedmueller@phytec.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>