usb: gadget: uvc: Allow creating new color matching descriptors

Allow users to create new color matching descriptors in addition to
the default one. These must be associated with a UVC format in order
to be transmitted to the host, which is achieved by symlinking from
the format to the newly created color matching descriptor - extend
the uncompressed and mjpeg formats to support that linking operation.

Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20230202114142.300858-7-dan.scally@ideasonboard.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>