docs/devel/qapi-code-gen: Update example to match current code

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221104160712.3005652-2-armbru@redhat.com>

docs/devel/qapi-code-gen.rst

@@ -1748,7 +1748,7 @@ Example::
         QTAILQ_INIT(cmds);
 
         qmp_register_command(cmds, "my-command",
-                             qmp_marshal_my_command, QCO_NO_OPTIONS);
+                             qmp_marshal_my_command, 0, 0);
     }
     [Uninteresting stuff omitted...]