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/video/cg6.c b/drivers/video/cg6.c
index 2389a71..2b5a970 100644
--- a/drivers/video/cg6.c
+++ b/drivers/video/cg6.c
@@ -718,7 +718,7 @@
 	sbus_writel(info->var.yres - 1, &fbc->clipmaxy);
 }
 
-static void cg6_unmap_regs(struct of_device *op, struct fb_info *info,
+static void cg6_unmap_regs(struct platform_device *op, struct fb_info *info,
 			   struct cg6_par *par)
 {
 	if (par->fbc)
@@ -737,7 +737,7 @@
 			   info->fix.smem_len);
 }
 
-static int __devinit cg6_probe(struct of_device *op,
+static int __devinit cg6_probe(struct platform_device *op,
 				const struct of_device_id *match)
 {
 	struct device_node *dp = op->dev.of_node;
@@ -827,7 +827,7 @@
 	return err;
 }
 
-static int __devexit cg6_remove(struct of_device *op)
+static int __devexit cg6_remove(struct platform_device *op)
 {
 	struct fb_info *info = dev_get_drvdata(&op->dev);
 	struct cg6_par *par = info->par;