ha: small wording tweaks on previous

(cherry picked from commit bb9daf3a)

src/www/status_habackup.php

@@ -172,7 +172,7 @@ include("head.inc");
     <div class="row">
 <?php
         if ($carp_backup_version === false):?>
-        <?=print_info_box(gettext("The backup firewall doesn't seem to be accesible or is not configured"));?>
+        <?=print_info_box(gettext('The backup firewall is not accessible or not configured.'));?>
 <?php
         elseif (!is_array($carp_backup_version)):?>
         <?=print_info_box(gettext('The backup firewall is not accessible (check user credentials).'));?>