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/spi/mpc52xx_psc_spi.c b/drivers/spi/mpc52xx_psc_spi.c
index 66d1701..983fbbf 100644
--- a/drivers/spi/mpc52xx_psc_spi.c
+++ b/drivers/spi/mpc52xx_psc_spi.c
@@ -465,7 +465,7 @@
 	return 0;
 }
 
-static int __init mpc52xx_psc_spi_of_probe(struct of_device *op,
+static int __init mpc52xx_psc_spi_of_probe(struct platform_device *op,
 	const struct of_device_id *match)
 {
 	const u32 *regaddr_p;
@@ -495,7 +495,7 @@
 				irq_of_parse_and_map(op->dev.of_node, 0), id);
 }
 
-static int __exit mpc52xx_psc_spi_of_remove(struct of_device *op)
+static int __exit mpc52xx_psc_spi_of_remove(struct platform_device *op)
 {
 	return mpc52xx_psc_spi_do_remove(&op->dev);
 }