This will create a host service principal and may create a host entry (for
admins). A keytab will be generated, by default in /etc/krb5.keytab
If no kerberos credentails are available then enrollment over LDAPS is used
if a password is provided.
This change requires that openldap be used as our C LDAP client. It is much
easier to do SSL using openldap than mozldap (no certdb required). Otherwise
we'd have to write a slew of extra code to create a temporary cert database,
import the CA cert, ...
