net: dsa: qca8k: check the correct variable in qca8k_set_mac_eee()

This code check "reg" but "ret" was intended so the error handling will
never trigger.

Fixes: 7c9896e3 ("net: dsa: qca8k: check return value of read functions correctly")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dsa/qca8k.c

@@ -1454,10 +1454,8 @@ qca8k_set_mac_eee(struct dsa_switch *ds, int port, struct ethtool_eee *eee)
 
 	mutex_lock(&priv->reg_mutex);
 	ret = qca8k_read(priv, QCA8K_REG_EEE_CTRL, &reg);
-	if (reg < 0) {
-		ret = reg;
+	if (ret < 0)
 		goto exit;
-	}
 
 	if (eee->eee_enabled)
 		reg |= lpi_en;