net: renesas: ravb: unintialized return value

We want to set the other "err" variable here so that we can return it
later.  My version of GCC misses this issue but I caught it with a
static checker.

Fixes: 9f70eb339f52 ("net: ethernet: renesas: ravb: fix fixed-link phydev leaks")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/ravb_main.c

@@ -1016,8 +1016,6 @@ static int ravb_phy_init(struct net_device *ndev)
 	 * at this time.
 	 */
 	if (priv->chip_id == RCAR_GEN3) {
-		int err;
-
 		err = phy_set_max_speed(phydev, SPEED_100);
 		if (err) {
 			netdev_err(ndev, "failed to limit PHY to 100Mbit/s\n");