Fix ipa migrate-ds when it finds a search reference
When ipa migrate-ds finds user entries and a search reference, it complains
that the LDAP search did not return any result and does not migrate the
entries or the groups.
The issue comes from LDAPClient._convert_result which returns an empty result
list when the input is a search reference. In turn LDAPClient.find_entries
assumes that the empty result list corresponds to a Search Result Done and
returns without any entry.
The fix examines first the objtype returned by self.conn.result3. If it is
a search result done, then the loop can be exited. Otherwise (referral or
entry), _convert_result is called and the result (if not empty) is appended
to the list of returned entries.
https://fedorahosted.org/freeipa/ticket/6358
Reviewed-By: Martin Basti <mbasti@redhat.com>