Restricting xen-set-global-dirty-log and xen-load-devices-state
commands migration.json pulls slightly less QAPI-generated code
into user-mode and tools.

Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201012121536.3381997-6-philmd@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>