vdpa: Avoid duplicate call to vp_vdpa get_status

It has no sense to call get_status twice, since we already have a
variable for that.
Signed-off-by: NEugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20211104195833.2089796-1-eperezma@redhat.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NJason Wang <jasowang@redhat.com>
Reviewed-by: NStefano Garzarella <sgarzare@redhat.com>

drivers/vhost/vdpa.c

@@ -170,7 +170,7 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
 	 * Userspace shouldn't remove status bits unless reset the
 	 * status to 0.
 	 */
-	if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
+	if (status != 0 && (status_old & ~status) != 0)
 		return -EINVAL;
 
 	if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK))