Avoid calling ldap functions without a context
We need to make sure we have a ld context before we can load the
configuration, otherwise ldap APIs will abort crashing the KDC.
If we have an issue connecting to LDAP the lcontext will be NULL, but
we are not checking that condition when we try to refresh the global
configuration.
https://fedorahosted.org/freeipa/ticket/4810
Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-By: Martin Kosek <mkosek@redhat.com>