set default session path from php settings

new_cp/application/config/config.php

@@ -380,7 +380,7 @@ $config['encryption_key'] = '';
 $config['sess_driver'] = 'files';
 $config['sess_cookie_name'] = 'typos_session';
 $config['sess_expiration'] = 7200;
-$config['sess_save_path'] = FCPATH . 'application/sessions/';
+$config['sess_save_path'] = NULL;
 $config['sess_match_ip'] = TRUE;
 $config['sess_time_to_update'] = 300;
 $config['sess_regenerate_destroy'] = FALSE;