gpio: gpio-mm-lantiq: Use of_mm_gpiochip_remove

Since d621e8bae5ac9c67 (Create of_mm_gpiochip_remove), there is a
counterpart for of_mm_gpiochip_add.

This patch implements the remove function of the driver making use of
it.

Cc: Alexandre Courbot <[e-mail]>
Cc: John Crispin <[e-mail]>
Signed-off-by: Ricardo Ribalda Delgado <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-mm-lantiq.c

···
 	if (!chip)
 		return -ENOMEM;
 
+	platform_set_drvdata(pdev, chip);
+
 	chip->mmchip.gc.ngpio = 16;
 	chip->mmchip.gc.direction_output = ltq_mm_dir_out;
 	chip->mmchip.gc.set = ltq_mm_set;
···
 	return of_mm_gpiochip_add(pdev->dev.of_node, &chip->mmchip);
 }
 
+static int ltq_mm_remove(struct platform_device *pdev)
+{
+	struct ltq_mm *chip = platform_get_drvdata(pdev);
+
+	of_mm_gpiochip_remove(&chip->mmchip);
+
+	return 0;
+}
+
 static const struct of_device_id ltq_mm_match[] = {
 	{ .compatible = "lantiq,gpio-mm" },
 	{},
···
 
 static struct platform_driver ltq_mm_driver = {
 	.probe = ltq_mm_probe,
+	.remove = ltq_mm_remove,
 	.driver = {
 		.name = "gpio-mm-ltq",
 		.of_match_table = ltq_mm_match,
···
 }
 
 subsys_initcall(ltq_mm_init);
+
+static void __exit ltq_mm_exit(void)
+{
+	platform_driver_unregister(&ltq_mm_driver);
+}
+module_exit(ltq_mm_exit);