check for existing fields when setting/updating tablelisting-columns

Signed-off-by: Michael Kaufmann <d00p@froxlor.org>

lib/tablelisting/customer/tablelisting.htaccess.php

@@ -27,6 +27,9 @@ use Froxlor\UI\Callbacks\Ftp;
 use Froxlor\UI\Callbacks\Text;
 use Froxlor\UI\Listing;
 
+// used outside scope variables
+$cperlenabled = $cperlenabled ?? false;
+
 return [
 	'htaccess_list' => [
 		'title' => lng('menue.extras.pathoptions'),

lib/tablelisting/customer/tablelisting.mysqls.php

@@ -27,6 +27,9 @@ use Froxlor\UI\Callbacks\Mysql;
 use Froxlor\UI\Callbacks\Text;
 use Froxlor\UI\Listing;
 
+// used outside scope variables
+$multiple_mysqlservers = $multiple_mysqlservers ?? false;
+
 return [
 	'mysql_list' => [
 		'title' => lng('menue.mysql.databases'),