Osticket: Sort error for banlist.inc.php

Under develop branch and 1.9.8.1 version(might other version also have the same error), line 113-116 in banlist.inc.php , the string "staff.php" should be changed to "banlist.php" .Otherwise ,the sort would not work which mentioned in issue #1725 .

            <th width="56%"><a <?php echo $email_sort; ?> href="staff.php?<?php echo $qstr; ?>&sort=email"><?php echo __('Email Address');?></a></th>
            <th width="10%"><a  <?php echo $status_sort; ?> href="staff.php?<?php echo $qstr; ?>&sort=status"><?php echo __('Ban Status');?></a></th>
            <th width="10%"><a <?php echo $created_sort; ?> href="staff.php?<?php echo $qstr; ?>&sort=created"><?php echo __('Date Added');?></a></th>
            <th width="20%"><a <?php echo $updated_sort; ?> href="staff.php?<?php echo $qstr; ?>&sort=updated"><?php echo __('Last Updated');?></a></th>

to

        <th width="56%"><a <?php echo $email_sort; ?> href="banlist.php?<?php echo $qstr; ?>&sort=email"><?php echo __('Email Address');?></a></th>
        <th width="10%"><a  <?php echo $status_sort; ?> href="banlist.php?<?php echo $qstr; ?>&sort=status"><?php echo __('Ban Status');?></a></th>
        <th width="10%"><a <?php echo $created_sort; ?> href="banlist.php?<?php echo $qstr; ?>&sort=created"><?php echo __('Date Added');?></a></th>
        <th width="20%"><a <?php echo $updated_sort; ?> href="banlist.php?<?php echo $qstr; ?>&sort=updated"><?php echo __('Last Updated');?></a></th>