watchdog: rt2880_wdt: fix return value check in rt288x_wdt_probe()

In case of error, the function devm_request_and_ioremap() returns NULL
pointer not ERR_PTR(). Fix it by using devm_ioremap_resource() instead
of devm_request_and_ioremap().

Signed-off-by: Wei Yongjun <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/rt2880_wdt.c

···
 	int ret;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	rt288x_wdt_base = devm_request_and_ioremap(&pdev->dev, res);
+	rt288x_wdt_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(rt288x_wdt_base))
 		return PTR_ERR(rt288x_wdt_base);