Fatal error: Can't use function return value in write context in /usr/www/users/salsasa/wp/wp-content/themes/enfold/header.php on line 6

Please Help,
that ist mein line 6 at header.php. Could you tell whats wrong:

<?php
if ( ! defined(‘ABSPATH’) ){ die(); }

global $avia_config;
THAT WILL BE MEIN LINE 6
$avia_config[‘use_standard_lightbox’] = empty( avia_get_option( ‘lightbox_active’ ) ) || ( ‘lightbox_active’ == avia_get_option( ‘lightbox_active’ ) ) ? ‘lightbox_active’ : ‘disabled’;
/**
* Allow to overwrite the option setting for using the standard lightbox
* Make sure to return ‘disabled’ to deactivate the standard lightbox – all checks are done against this string