Notice: rss.php is deprecated since version 3.0!

Hi I have an deprecated error.

Which is following :
Notice: rss.php is deprecated since version 3.0! Use wp-includes/class-simplepie.php instead. in /home/defatch/public_html/themes/versatile/wp-includes/functions.php on line 3134

Thanks!

https://wordpress.org/plugins/shortcodes-ultimate/