of/platform: remove all of_bus_type and of_platform_bus_type references

Both of_bus_type and of_platform_bus_type are just #define aliases
for the platform bus.  This patch removes all references to them and
switches to the of_register_platform_driver()/of_unregister_platform_driver()
API for registering.

Subsequent patches will convert each user of of_register_platform_driver()
into plain platform_drivers without the of_platform_driver shim.  At which
point the of_register_platform_driver()/of_unregister_platform_driver()
functions can be removed.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/crypto/n2_core.c b/drivers/crypto/n2_core.c
index 23163fd..34ac8ac 100644
--- a/drivers/crypto/n2_core.c
+++ b/drivers/crypto/n2_core.c
@@ -2070,20 +2070,20 @@
 
 static int __init n2_init(void)
 {
-	int err = of_register_driver(&n2_crypto_driver, &of_bus_type);
+	int err = of_register_platform_driver(&n2_crypto_driver);
 
 	if (!err) {
-		err = of_register_driver(&n2_mau_driver, &of_bus_type);
+		err = of_register_platform_driver(&n2_mau_driver);
 		if (err)
-			of_unregister_driver(&n2_crypto_driver);
+			of_unregister_platform_driver(&n2_crypto_driver);
 	}
 	return err;
 }
 
 static void __exit n2_exit(void)
 {
-	of_unregister_driver(&n2_mau_driver);
-	of_unregister_driver(&n2_crypto_driver);
+	of_unregister_platform_driver(&n2_mau_driver);
+	of_unregister_platform_driver(&n2_crypto_driver);
 }
 
 module_init(n2_init);