Fix broadcast-message queries to work with postgresql

This is a follow-up fix as discussed on
https://github.com/postfixadmin/postfixadmin/pull/50

broadcast-message.php

@@ -61,9 +61,9 @@ if ($_SERVER['REQUEST_METHOD'] == "POST")
 
       $recipients = [];
 
-      $q = "SELECT username, active from $table_mailbox WHERE active=1 AND ".db_in_clause("domain", $wanted_domains);
+      $q = "SELECT username from $table_mailbox WHERE active='" . db_get_boolean(true) . "' AND ".db_in_clause("domain", $wanted_domains);
       if (intval(safepost('mailboxes_only')) == 0) {
-         $q .= " UNION SELECT goto, active FROM $table_alias WHERE ".db_in_clause("domain", $wanted_domains)."AND goto NOT IN ($q)";
+         $q .= " UNION SELECT goto FROM $table_alias WHERE active='" . db_get_boolean(true) . "' AND ".db_in_clause("domain", $wanted_domains)."AND goto NOT IN ($q)";
       }
       $result = db_query($q);
       if($result['rows'] > 0) {