KDC autodiscovery may fail when domain is not realm
When ipa-client-install autodiscovers IPA server values it
doesn't fill the fixed KDC address to Kerberos configuration
file. However, when realm != domain or the autodiscovered values
are overridden, installation may fail because it cannot find the
KDC.
This patch adds a failover to use static KDC address in case when
such an issue occurs.
https://fedorahosted.org/freeipa/ticket/1100