net: ks8851: Check for error irq

Because platform_get_irq() could fail and return error irq.
Therefore, it might be better to check it if order to avoid the use of
error irq.

Fixes: 797047f8 ("net: ks8851: Implement Parallel bus operations")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/micrel/ks8851_par.c

@@ -321,6 +321,8 @@ static int ks8851_probe_par(struct platform_device *pdev)
 		return ret;
 
 	netdev->irq = platform_get_irq(pdev, 0);
+	if (netdev->irq < 0)
+		return netdev->irq;
 
 	return ks8851_probe_common(netdev, dev, msg_enable);
 }