AccessControlAction: minor improvement when user or group privileges are empty

if (groupPrivilegeNames.length == 0 && userPrivilegeNames.length == 0) {
            log.debug("No privileges configured for groups and users; omit ac setup.");
            return;
        }

if (groupPrivilegeNames.length == 0 && authorizable.isGroup()) {
    // log + return
} else if (userPrivilegeNames.length == 0 && !authorizable.isGroup()) {
   // log + return
}