s4:rpc_server/netlogon: use samdb_domain_guid()/dsdb_trust_local_tdo_info() to build...

s4:rpc_server/netlogon: use samdb_domain_guid()/dsdb_trust_local_tdo_info() to build our netr_OneDomainInfo values

The logic for constructing the values for our own primary domain differs
from the values of trusted domains. In order to make the code easier to
understand we have a new fill_our_one_domain_info() helper that
only takes care of our primary domain.

The cleanup for the trust case will follow in a separate commit.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11517

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>