media: uapi: Introduce V4L2 generic ISP types

media: uapi: Introduce V4L2 generic ISP types

Introduce v4l2-isp.h in the Linux kernel uAPI.

The header includes types for generic ISP configuration parameters
and will be extended in the future with support for generic ISP statistics
formats.

Generic ISP parameters support is provided by introducing two new
types that represent an extensible and versioned buffer of ISP
configuration parameters.

The v4l2_params_buffer represents the container for the ISP
configuration data block. The generic type is defined with a 0-sized
data member that the ISP driver implementations shall properly size
according to their capabilities. The v4l2_params_block_header structure
represents the header to be prepend to each ISP configuration block.

Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Michael Riesch <michael.riesch@collabora.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>