gpio/rockchip: fix refcount leak in rockchip_gpiolib_register()

The node returned by of_get_parent() with refcount incremented,
of_node_put() needs be called when finish using it. So add it in the
end of of_pinctrl_get().

Fixes: 936ee2675e ("gpio/rockchip: add driver for rockchip gpio")
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-rockchip.c

@@ -610,6 +610,7 @@ static int rockchip_gpiolib_register(struct rockchip_pin_bank *bank)
 			return -ENODATA;
 
 		pctldev = of_pinctrl_get(pctlnp);
+		of_node_put(pctlnp);
 		if (!pctldev)
 			return -ENODEV;