phy: safer to_phy() macro

This makes to_phy() macro work with other variable names
besides "dev".

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Vivek Gautam <gautam.vivek@samsung.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

include/linux/phy/phy.h

@@ -110,7 +110,7 @@ struct phy_init_data {
 	.port		= _port,				\
 }
 
-#define	to_phy(dev)	(container_of((dev), struct phy, dev))
+#define	to_phy(a)	(container_of((a), struct phy, dev))
 
 #define	of_phy_provider_register(dev, xlate)	\
 	__of_phy_provider_register((dev), THIS_MODULE, (xlate))