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/usb/host/ehci-ppc-of.c b/drivers/usb/host/ehci-ppc-of.c
index 8df33b8..ad06623 100644
--- a/drivers/usb/host/ehci-ppc-of.c
+++ b/drivers/usb/host/ehci-ppc-of.c
@@ -108,7 +108,7 @@
 static int __devinit
 ehci_hcd_ppc_of_probe(struct of_device *op, const struct of_device_id *match)
 {
-	struct device_node *dn = op->node;
+	struct device_node *dn = op->dev.of_node;
 	struct usb_hcd *hcd;
 	struct ehci_hcd	*ehci = NULL;
 	struct resource res;