net: phy: smsc: fix clk error handling

Commit bedd8d78 ("net: phy: smsc: LAN8710/20: add phy refclk in
support") added the phy clk support. The commit already checks if
clk_get_optional() throw an error but instead of returning the error it
ignores it.

Fixes: bedd8d78 ("net: phy: smsc: LAN8710/20: add phy refclk in support")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20210111085932.28680-1-m.felsch@pengutronix.deSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/smsc.c

@@ -317,7 +317,8 @@ static int smsc_phy_probe(struct phy_device *phydev)
 	/* Make clk optional to keep DTB backward compatibility. */
 	priv->refclk = clk_get_optional(dev, NULL);
 	if (IS_ERR(priv->refclk))
-		dev_err_probe(dev, PTR_ERR(priv->refclk), "Failed to request clock\n");
+		return dev_err_probe(dev, PTR_ERR(priv->refclk),
+				     "Failed to request clock\n");
 
 	ret = clk_prepare_enable(priv->refclk);
 	if (ret)