watchdog: mpcore_wdt: Allow platform_get_irq() to fail

irq is not necessary for mpcore wdt. Don't return error if it is not passed. But
if it is passed, then request_irq must pass.
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/mpcore_wdt.c

@@ -347,16 +347,16 @@ static int __devinit mpcore_wdt_probe(struct platform_device *pdev)
 
 	wdt->dev = &pdev->dev;
 	wdt->irq = platform_get_irq(pdev, 0);
-	if (wdt->irq < 0)
-		return -ENXIO;
-
+	if (wdt->irq >= 0) {
 		ret = devm_request_irq(wdt->dev, wdt->irq, mpcore_wdt_fire, 0,
 				"mpcore_wdt", wdt);
 		if (ret) {
 			dev_printk(KERN_ERR, wdt->dev,
-			"cannot register IRQ%d for watchdog\n", wdt->irq);
+					"cannot register IRQ%d for watchdog\n",
+					wdt->irq);
 			return ret;
 		}
+	}
 
 	wdt->base = devm_ioremap(wdt->dev, res->start, resource_size(res));
 	if (!wdt->base)