use new allow-preconfig parameter in tests and make sure that
the QAPISchema can parse allow-preconfig correctly
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1526058959-41425-1-git-send-email-imammedo@redhat.com>
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>