Each KDC is a kx509 server. The service principal must be of the
form
kca_service/<localhost.domain>@<DEFAULT_REALM>
where localhost.domain is the hostname returned by gethostname()
and <DEFAULT_REALM> is one of the realms for which the KDC has a service
principal "kca_service/<localhost.domain>".
The matching code was broken by a5e77c578e
when krb5_sname_to_principal() began to always return a referral
principal.
Since the second component is a host name update the default principal
type for service "kca_service" to be KRB5_NT_SRV_HST.
Change-Id: I6bd5f90b674ebb7220d8efafa6d339fdc21e1a07
ec39b832ff