watchdog: qcom: Check for platform_get_resource() failure

platform_get_resource() may fail, so we should better check its
return value and propagate an error in case it fails.

This avoids a NULL pointer dereference a bit later in the code.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

drivers/watchdog/qcom-wdt.c

@@ -162,6 +162,8 @@ static int qcom_wdt_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENOMEM;
 
 	/* We use CPU0's DGT for the watchdog */
 	if (of_property_read_u32(np, "cpu-offset", &percpu_offset))