net: phy: smsc: add missed clk_disable_unprepare in smsc_phy_probe()

Add the missing clk_disable_unprepare() before return from
smsc_phy_probe() in the error handling case.

Fixes: bedd8d7 ("net: phy: smsc: LAN8710/20: add phy refclk in support")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Link: https://lore.kernel.org/r/1605180239-1792-1-git-send-email-zhangchangzhong@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/smsc.c

@@ -291,8 +291,10 @@ static int smsc_phy_probe(struct phy_device *phydev)
 		return ret;
 
 	ret = clk_set_rate(priv->refclk, 50 * 1000 * 1000);
-	if (ret)
+	if (ret) {
+		clk_disable_unprepare(priv->refclk);
 		return ret;
+	}
 
 	return 0;
 }