[ARM] am79c961a: platform_get_irq() may return signed unnoticed

dev->irq is unsigned, platform_get_irq() may return signed unnoticed
Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/net/arm/am79c961a.c

@@ -693,11 +693,15 @@ static int __init am79c961_probe(struct platform_device *pdev)
 	 * done by the ether bootp loader.
 	 */
 	dev->base_addr = res->start;
-	dev->irq = platform_get_irq(pdev, 0);
+	ret = platform_get_irq(pdev, 0);
 
-	ret = -ENODEV;
-	if (dev->irq < 0)
+	if (ret < 0) {
+		ret = -ENODEV;
 		goto nodev;
+	}
+	dev->irq = ret;
+
+	ret = -ENODEV;
 	if (!request_region(dev->base_addr, 0x18, dev->name))
 		goto nodev;