xen/dmabuf: switch gntdev-dmabuf to use INVALID_GRANT_REF

Instead of using a private macro for an invalid grant reference use
the common one.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
This commit is contained in:
Juergen Gross 2022-04-28 09:01:03 +02:00
commit bd506c7812