dns/bind: Fix handling of multiple ACLs in allow-query/allow-transfer

[NHellFire]

Selecting multiple ACLs under the General tab currently results in invalid config:

        allow-transfer {
                ;
        };

        allow-query {
                ;
        };

This corrects the behaviour:

        allow-recursion {
                LAN;
                VPN;
        };

        allow-query {
                LAN;
                VPN;
        };

[fichtner]

Nice catch... toList() is supposed to be used for repeating nested items, not single value items. Thanks!