mtd: rawnand: omap2: 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/20200519130035.1883-33-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/omap2.c

@@ -2283,14 +2283,18 @@ static int omap_nand_remove(struct platform_device *pdev)
 	struct mtd_info *mtd = platform_get_drvdata(pdev);
 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
 	struct omap_nand_info *info = mtd_to_omap(mtd);
+	int ret;
+
 	if (nand_chip->ecc.priv) {
 		nand_bch_free(nand_chip->ecc.priv);
 		nand_chip->ecc.priv = NULL;
 	}
 	if (info->dma)
 		dma_release_channel(info->dma);
-	nand_release(nand_chip);
-	return 0;
+	ret = mtd_device_unregister(mtd);
+	WARN_ON(ret);
+	nand_cleanup(nand_chip);
+	return ret;
 }
 
 static const struct of_device_id omap_nand_ids[] = {