virtio_mmio: add support to set IRQ of a virtio device as wakeup source

According to virtio_mmio wakeup flag in device trees, set its IRQ
as wakeup source in virtqueue initialization.
Signed-off-by: Minghao Xue <quic_mingxue@quicinc.com>
Message-Id: <1654851507-13891-3-git-send-email-quic_mingxue@quicinc.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_mmio.c

@@ -487,6 +487,9 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned int nvqs,
 	if (err)
 		return err;
 
+	if (of_property_read_bool(vm_dev->pdev->dev.of_node, "wakeup-source"))
+		enable_irq_wake(irq);
+
 	for (i = 0; i < nvqs; ++i) {
 		if (!names[i]) {
 			vqs[i] = NULL;