net: systemport: Fix an error handling path in bcm_sysport_probe()

if devm_clk_get_optional() fails, we still need to go through the error
handling path.

Add the missing goto.

Fixes: 6328a126 ("net: systemport: Manage Wake-on-LAN clock")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/99d70634a81c229885ae9e4ee69b2035749f7edc.1652634040.git.christophe.jaillet@wanadoo.frSigned-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/broadcom/bcmsysport.c

@@ -2585,8 +2585,10 @@ static int bcm_sysport_probe(struct platform_device *pdev)
 		device_set_wakeup_capable(&pdev->dev, 1);
 
 	priv->wol_clk = devm_clk_get_optional(&pdev->dev, "sw_sysportwol");
-	if (IS_ERR(priv->wol_clk))
-		return PTR_ERR(priv->wol_clk);
+	if (IS_ERR(priv->wol_clk)) {
+		ret = PTR_ERR(priv->wol_clk);
+		goto err_deregister_fixed_link;
+	}
 
 	/* Set the needed headroom once and for all */
 	BUILD_BUG_ON(sizeof(struct bcm_tsb) != 8);