mtd: rawnand: ams-delta: Stop using nand_release()

This helper is not very useful and very often people get confused:
they use nand_release() instead of nand_cleanup().

Let's stop using nand_release() by calling mtd_device_unregister() and
nand_cleanup() directly.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-2-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/ams-delta.c

@@ -387,12 +387,15 @@ static int gpio_nand_remove(struct platform_device *pdev)
 {
 	struct gpio_nand *priv = platform_get_drvdata(pdev);
 	struct mtd_info *mtd = nand_to_mtd(&priv->nand_chip);
+	int ret;
 
 	/* Apply write protection */
 	gpiod_set_value(priv->gpiod_nwp, 1);
 
 	/* Unregister device */
-	nand_release(mtd_to_nand(mtd));
+	ret = mtd_device_unregister(mtd);
+	WARN_ON(ret);
+	nand_cleanup(mtd_to_nand(mtd));
 
 	return 0;
 }