gpio: of: correct notifier return codes

According to the comments in linux/notifier.h, the code to return when a
notifications is "not for us" is NOTIFY_DONE, not NOTIFY_OK.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-of.c

@@ -834,14 +834,14 @@ static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
 	switch (of_reconfig_get_state_change(action, arg)) {
 	case OF_RECONFIG_CHANGE_ADD:
 		if (!of_property_read_bool(rd->dn, "gpio-hog"))
-			return NOTIFY_OK;	/* not for us */
+			return NOTIFY_DONE;	/* not for us */
 
 		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
-			return NOTIFY_OK;
+			return NOTIFY_DONE;
 
 		chip = of_find_gpiochip_by_node(rd->dn->parent);
 		if (chip == NULL)
-			return NOTIFY_OK;	/* not for us */
+			return NOTIFY_DONE;	/* not for us */
 
 		ret = of_gpiochip_add_hog(chip, rd->dn);
 		if (ret < 0) {
@@ -850,22 +850,22 @@ static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
 			of_node_clear_flag(rd->dn, OF_POPULATED);
 			return notifier_from_errno(ret);
 		}
-		break;
+		return NOTIFY_OK;
 
 	case OF_RECONFIG_CHANGE_REMOVE:
 		if (!of_node_check_flag(rd->dn, OF_POPULATED))
-			return NOTIFY_OK;	/* already depopulated */
+			return NOTIFY_DONE;	/* already depopulated */
 
 		chip = of_find_gpiochip_by_node(rd->dn->parent);
 		if (chip == NULL)
-			return NOTIFY_OK;	/* not for us */
+			return NOTIFY_DONE;	/* not for us */
 
 		of_gpiochip_remove_hog(chip, rd->dn);
 		of_node_clear_flag(rd->dn, OF_POPULATED);
-		break;
+		return NOTIFY_OK;
 	}
 
-	return NOTIFY_OK;
+	return NOTIFY_DONE;
 }
 
 struct notifier_block gpio_of_notifier = {