greybus: camera: Rename debug and metadata mbus formats

Change ARA prefix to GB_CAM for greyus camera specific
formats.

Change-Id: I1a0552516e8ea727c48085c59fc49f2409a89486
Signed-off-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Signed-off-by: Blagovest Borisov Kolenichev <kolenichev_blagovest@projectara.com>
Acked-by: Laurent Pinchart <laurent.pinchart@linaro.org>