of/device: Replace struct of_device with struct platform_device

of_device is just an alias for platform_device, so remove it entirely.  Also
replace to_of_device() with to_platform_device() and update comment blocks.

This patch was initially generated from the following semantic patch, and then
edited by hand to pick up the bits that coccinelle didn't catch.

@@
@@
-struct of_device
+struct platform_device

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/niu.c b/drivers/net/niu.c
index 404f2d55..bc695d5 100644
--- a/drivers/net/niu.c
+++ b/drivers/net/niu.c
@@ -9103,7 +9103,7 @@
 static int __devinit niu_n2_irq_init(struct niu *np, u8 *ldg_num_map)
 {
 #ifdef CONFIG_SPARC64
-	struct of_device *op = np->op;
+	struct platform_device *op = np->op;
 	const u32 *int_prop;
 	int i;
 
@@ -9688,7 +9688,7 @@
 
 static struct net_device * __devinit niu_alloc_and_init(
 	struct device *gen_dev, struct pci_dev *pdev,
-	struct of_device *op, const struct niu_ops *ops,
+	struct platform_device *op, const struct niu_ops *ops,
 	u8 port)
 {
 	struct net_device *dev;
@@ -10064,7 +10064,7 @@
 	.unmap_single	= niu_phys_unmap_single,
 };
 
-static int __devinit niu_of_probe(struct of_device *op,
+static int __devinit niu_of_probe(struct platform_device *op,
 				  const struct of_device_id *match)
 {
 	union niu_parent_id parent_id;
@@ -10179,7 +10179,7 @@
 	return err;
 }
 
-static int __devexit niu_of_remove(struct of_device *op)
+static int __devexit niu_of_remove(struct platform_device *op)
 {
 	struct net_device *dev = dev_get_drvdata(&op->dev);