media: v4l2_ctrl: Add V4L2_CTRL_TYPE_RECT

Add p_rect to struct v4l2_ext_control with basic support in
v4l2-ctrls.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Yunke Cao <yunkec@google.com>
Reviewed-by: Hans Verkuil <hverkuil@xs4all.nl>
Tested-by: Yunke Cao <yunkec@google.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Link: https://lore.kernel.org/r/20250203-uvc-roi-v17-1-5900a9fed613@chromium.org


Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>