The pkgsrc repository in git for DragonFly is currently frozen. This is because many people have switched over to dports, and also because it’s a lot of work to keep it functional. If you do want to pull newer pkgsrc material, use cvs and grab it from a NetBSD server.
As the message notes, don’t go switching to DragonFly-current right now, cause there’s a lot of new material in there and it may not be quite safe. (There’s an ABI change that will require all new builds of your ports, for instance.)