dsinstance: enable ldapi and autobind in ds
    
    * enable ldapi and root autobind early during the ds installation
    * perform these changes using simple_bind with dm_password
    
    https://fedorahosted.org/freeipa/ticket/6461
    
    Reviewed-By: Martin Basti <mbasti@redhat.com>
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>