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/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 6545d1c..a1c419a 100644
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -560,7 +560,7 @@
 	.timeout = HZ,
 };
 
-static int __devinit fsl_i2c_probe(struct of_device *op,
+static int __devinit fsl_i2c_probe(struct platform_device *op,
 				   const struct of_device_id *match)
 {
 	struct mpc_i2c *i2c;
@@ -646,7 +646,7 @@
 	return result;
 };
 
-static int __devexit fsl_i2c_remove(struct of_device *op)
+static int __devexit fsl_i2c_remove(struct platform_device *op)
 {
 	struct mpc_i2c *i2c = dev_get_drvdata(&op->dev);