net: of_mdio: don't store the length of a property if we don't need to

of_get_property() can be called with NULL as 2nd argument if the caller
is not interested in the length of a property. Use that here so we can
get rid of a variable.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/of/of_mdio.c

@@ -123,7 +123,7 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 	const __be32 *paddr;
 	u32 addr;
 	bool scanphys = false;
-	int rc, i, len;
+	int rc, i;
 
 	/* Mask out all PHYs from auto probing.  Instead the PHYs listed in
 	 * the device tree are populated after the bus has been registered */
@@ -160,7 +160,7 @@ int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
 	/* auto scan for PHYs with empty reg property */
 	for_each_available_child_of_node(np, child) {
 		/* Skip PHYs with reg property set */
-		paddr = of_get_property(child, "reg", &len);
+		paddr = of_get_property(child, "reg", NULL);
 		if (paddr)
 			continue;