net: ethernet: ti: cpsw: Fix inconsistent IS_ERR and PTR_ERR in cpsw_probe()

Fix inconsistent IS_ERR and PTR_ERR in cpsw_probe,
The proper pointer to use is clk instead of mode.

This issue was detected with the help of Coccinelle.

Fixes: 83a8471b ("net: ethernet: ti: cpsw: refactor probe to group common hw initialization")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ti/cpsw.c

@@ -2381,7 +2381,7 @@ static int cpsw_probe(struct platform_device *pdev)
 
 	clk = devm_clk_get(dev, "fck");
 	if (IS_ERR(clk)) {
-		ret = PTR_ERR(mode);
+		ret = PTR_ERR(clk);
 		dev_err(dev, "fck is not found %d\n", ret);
 		return ret;
 	}