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/net/ibm_newemac/rgmii.h b/drivers/net/ibm_newemac/rgmii.h
index c4a4b35..d697990 100644
--- a/drivers/net/ibm_newemac/rgmii.h
+++ b/drivers/net/ibm_newemac/rgmii.h
@@ -51,20 +51,20 @@
 	int				users;
 
 	/* OF device instance */
-	struct of_device		*ofdev;
+	struct platform_device		*ofdev;
 };
 
 #ifdef CONFIG_IBM_NEW_EMAC_RGMII
 
 extern int rgmii_init(void);
 extern void rgmii_exit(void);
-extern int rgmii_attach(struct of_device *ofdev, int input, int mode);
-extern void rgmii_detach(struct of_device *ofdev, int input);
-extern void rgmii_get_mdio(struct of_device *ofdev, int input);
-extern void rgmii_put_mdio(struct of_device *ofdev, int input);
-extern void rgmii_set_speed(struct of_device *ofdev, int input, int speed);
-extern int rgmii_get_regs_len(struct of_device *ofdev);
-extern void *rgmii_dump_regs(struct of_device *ofdev, void *buf);
+extern int rgmii_attach(struct platform_device *ofdev, int input, int mode);
+extern void rgmii_detach(struct platform_device *ofdev, int input);
+extern void rgmii_get_mdio(struct platform_device *ofdev, int input);
+extern void rgmii_put_mdio(struct platform_device *ofdev, int input);
+extern void rgmii_set_speed(struct platform_device *ofdev, int input, int speed);
+extern int rgmii_get_regs_len(struct platform_device *ofdev);
+extern void *rgmii_dump_regs(struct platform_device *ofdev, void *buf);
 
 #else