vhost_vdpa: unset vq irq before freeing irq

Currently we unset vq irq after freeing irq and that will result in
error messages:

  pi_update_irte: failed to update PI IRTE
  irq bypass consumer (token 000000005a07a12b) unregistration fails: -22

This patch solves this.
Signed-off-by: NWu Zongyong <wuzongyong@linux.alibaba.com>
Link: https://lore.kernel.org/r/02637d38dcf4e4b836c5b3a65055fe92bf812b3b.1631687872.git.wuzongyong@linux.alibaba.comSigned-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NJason Wang <jasowang@redhat.com>

drivers/vhost/vdpa.c

@@ -173,6 +173,10 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
 	if (status != 0 && (ops->get_status(vdpa) & ~status) != 0)
 		return -EINVAL;
 
+	if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK))
+		for (i = 0; i < nvqs; i++)
+			vhost_vdpa_unsetup_vq_irq(v, i);
+
 	if (status == 0) {
 		ret = ops->reset(vdpa);
 		if (ret)
@@ -184,10 +188,6 @@ static long vhost_vdpa_set_status(struct vhost_vdpa *v, u8 __user *statusp)
 		for (i = 0; i < nvqs; i++)
 			vhost_vdpa_setup_vq_irq(v, i);
 
-	if ((status_old & VIRTIO_CONFIG_S_DRIVER_OK) && !(status & VIRTIO_CONFIG_S_DRIVER_OK))
-		for (i = 0; i < nvqs; i++)
-			vhost_vdpa_unsetup_vq_irq(v, i);
-
 	return 0;
 }