Bogus reply if ldap query is empty

[Sven Hartge]

Hi *,

I just deployed a test-setup of automx using the LDAP backend.

I noticed one oddity: If the query yields no result (because, for
example, the user mistyped his mail-address), then a bogus XML is
returned to the client.

For example the <username></username> is empty, the displayname is
empty, because the macros where empty, because the LDAP query was
without results.

I think in that case automx should not reply with any configuration.

Grüße,
Sven.