obj: objects can now be published in the namespace root

obj/namespace.c

@@ -105,7 +105,7 @@ kern_status_t object_publish(object_namespace_t *ns, const char *path, object_t
 
 	size_t path_len = strlen(path);
 	if (path_len == 0) {
-		return KERN_INVALID_ARGUMENT;
+		return set_add_object(ns->ns_root, obj);
 	}
 
 	size_t parts = 0;