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>

drivers/net/sunqe.h

@@ -314,7 +314,7 @@ struct sunqec {
 	void __iomem		*gregs;		/* QEC Global Registers         */
 	struct sunqe		*qes[4];	/* Each child MACE              */
 	unsigned int            qec_bursts;	/* Support burst sizes          */
-	struct of_device	*op;		/* QEC's OF device              */
+	struct platform_device	*op;		/* QEC's OF device              */
 	struct sunqec		*next_module;	/* List of all QECs in system   */
 };
 
@@ -342,7 +342,7 @@ struct sunqe {
 	__u32				buffers_dvma;	/* DVMA visible address.       */
 	struct sunqec			*parent;
 	u8				mconfig;	/* Base MACE mconfig value     */
-	struct of_device		*op;		/* QE's OF device struct       */
+	struct platform_device		*op;		/* QE's OF device struct       */
 	struct net_device		*dev;		/* QE's netdevice struct       */
 	int				channel;	/* Who am I?                   */
 };