Fix ipa-replica-install when upgrade from ca-less to ca-full
When ipa-replica-prepare is run on a master upgraded from CA-less to
CA-full, it creates the replica file with a copy of the local /etc/ipa/ca.crt.
This causes issues if this file hasn't been updated with ipa-certupdate,
as it contains the external CA that signed http/ldap certs, but not
the newly installed IPA CA.
As a consequence, ipa-replica-install fails with "Could not find a CA cert".
The fix consists in retrieving the CA certificates from LDAP instead of
the local /etc/ipa/ca.crt.
https://fedorahosted.org/freeipa/ticket/6375
Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>
Reviewed-By: Tomas Krizek <tkrizek@redhat.com>