qapi: Add some enum tests Demonstrate that the qapi generator doesn't deal well with enums that aren't up to par. Later patches will update the expected results as the generator is made stricter. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>