watchdog: ep93xx_wdt: Use devm_ioremap_resource()

Use devm_ioremap_resource() in order to make the code simpler,
and remove redundant return value check of platform_get_resource()
because the value is checked by devm_ioremap_resource().
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/ep93xx_wdt.c

@@ -118,16 +118,9 @@ static int ep93xx_wdt_probe(struct platform_device *pdev)
 	int err;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res)
-		return -ENXIO;
-
-	if (!devm_request_mem_region(&pdev->dev, res->start,
-				     resource_size(res), pdev->name))
-		return -EBUSY;
-
-	mmio_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
-	if (!mmio_base)
-		return -ENXIO;
+	mmio_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mmio_base))
+		return PTR_ERR(mmio_base);
 
 	if (timeout < 1 || timeout > 3600) {
 		timeout = WDT_TIMEOUT;