greybus: camera: Add debug data format

Add support for greybus debug data format.
Greybus debug data format id is 0x42.

Signed-off-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Acked-by: Laurent Pinchart <laurent.pinchart@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>