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/xilinx_spi_of.c b/drivers/spi/xilinx_spi_of.c
index f53d3f6..b66c2db 100644
--- a/drivers/spi/xilinx_spi_of.c
+++ b/drivers/spi/xilinx_spi_of.c
@@ -38,7 +38,7 @@
 #include "xilinx_spi.h"
 
 
-static int __devinit xilinx_spi_of_probe(struct of_device *ofdev,
+static int __devinit xilinx_spi_of_probe(struct platform_device *ofdev,
 	const struct of_device_id *match)
 {
 	struct spi_master *master;
@@ -84,7 +84,7 @@
 	return 0;
 }
 
-static int __devexit xilinx_spi_remove(struct of_device *ofdev)
+static int __devexit xilinx_spi_remove(struct platform_device *ofdev)
 {
 	xilinx_spi_deinit(dev_get_drvdata(&ofdev->dev));
 	dev_set_drvdata(&ofdev->dev, 0);
@@ -93,7 +93,7 @@
 	return 0;
 }
 
-static int __exit xilinx_spi_of_remove(struct of_device *op)
+static int __exit xilinx_spi_of_remove(struct platform_device *op)
 {
 	return xilinx_spi_remove(op);
 }