watchdog: gpio_wdt: Fix missing platform_set_drvdata() in gpio_wdt_probe()

Add missing platform_set_drvdata() in gpio_wdt_probe(), otherwise
calling platform_get_drvdata() in remove returns NULL.

This is detected by Coccinelle semantic patch.

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

drivers/watchdog/gpio_wdt.c

@@ -151,6 +151,8 @@ static int gpio_wdt_probe(struct platform_device *pdev)
 	if (!priv)
 		return -ENOMEM;
 
+	platform_set_drvdata(pdev, priv);
+
 	priv->gpio = of_get_gpio_flags(pdev->dev.of_node, 0, &flags);
 	if (!gpio_is_valid(priv->gpio))
 		return priv->gpio;