fixed issue where accessing a category's access control caused a client-side error

src/socket.io/admin/categories.js

@@ -68,7 +68,7 @@ Categories.getPrivilegeSettings = function(socket, cid, callback) {
 	async.reduce(privileges, [], function(members, privilege, next) {
 		groups.get('cid:' + cid + ':privileges:' + privilege, { expand: true }, function(err, groupObj) {
 			if (err || !groupObj) {
-				return next(err, members);
+				return next(null, members);
 			}
 
 			members = members.concat(groupObj.members);