samba-tool dns: Don't use "localhost" to connect to local host

samba-tool dns: Don't use "localhost" to connect to local host

Calling "samba-tool dns <cmd> localhost" provokes a stacktrace.

This just makes 'samba-tool dns <cmd> localhost' work and doesn't fix
the underlying issue, but I don't see it causing any harm (unless you
don't have an ipv4 localhost, I guess).

Signed-off-by: Kai Blin <kai@samba.org>
Reviewed-by: Michael Adam <obnox@samba.org>
Autobuild-User(master): Michael Adam <obnox@samba.org>
Autobuild-Date(master): Fri Nov 16 13:18:14 CET 2012 on sn-devel-104