cirrus: cs89x0: fix the return value handle and remove redundant dev_warn() for platform_get_irq()

There is no possible for platform_get_irq() to return 0
and the return value of platform_get_irq() is more sensible
to show the error reason.

And there is no need to call the dev_warn() function directly to print
a custom message when handling an error from platform_get_irq() function as
it is going to display an appropriate error message in case of a failure.
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20230801133121.416319-1-ruanjinjie@huawei.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/cirrus/cs89x0.c

@@ -1854,9 +1854,8 @@ static int __init cs89x0_platform_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	dev->irq = platform_get_irq(pdev, 0);
-	if (dev->irq <= 0) {
-		dev_warn(&dev->dev, "interrupt resource missing\n");
-		err = -ENXIO;
+	if (dev->irq < 0) {
+		err = dev->irq;
 		goto free;
 	}