mtd: rawnand: mpc5121: 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/20200519130035.1883-27-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/mpc5121_nfc.c

@@ -805,8 +805,11 @@ static int mpc5121_nfc_remove(struct platform_device *op)
 {
 	struct device *dev = &op->dev;
 	struct mtd_info *mtd = dev_get_drvdata(dev);
+	int ret;
 
-	nand_release(mtd_to_nand(mtd));
+	ret = mtd_device_unregister(mtd);
+	WARN_ON(ret);
+	nand_cleanup(mtd_to_nand(mtd));
 	mpc5121_nfc_free(dev, mtd);
 
 	return 0;