of: Always use 'struct device.of_node' to get device node pointer.

The following structure elements duplicate the information in
'struct device.of_node' and so are being eliminated.  This patch
makes all readers of these elements use device.of_node instead.

(struct of_device *)->node
(struct dev_archdata *)->prom_node (sparc)
(struct dev_archdata *)->of_node (powerpc & microblaze)

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/drivers/cdrom/viocd.c b/drivers/cdrom/viocd.c
index cc435be..451cd70 100644
--- a/drivers/cdrom/viocd.c
+++ b/drivers/cdrom/viocd.c
@@ -567,7 +567,7 @@
 	struct disk_info *d;
 	struct cdrom_device_info *c;
 	struct request_queue *q;
-	struct device_node *node = vdev->dev.archdata.of_node;
+	struct device_node *node = vdev->dev.of_node;
 
 	deviceno = vdev->unit_address;
 	if (deviceno >= VIOCD_MAX_CD)