mtd: rawnand: fsl_upm: 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/20200519130035.1883-17-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/fsl_upm.c

@@ -317,10 +317,13 @@ static int fun_probe(struct platform_device *ofdev)
 static int fun_remove(struct platform_device *ofdev)
 {
 	struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
-	struct mtd_info *mtd = nand_to_mtd(&fun->chip);
-	int i;
+	struct nand_chip *chip = &fun->chip;
+	struct mtd_info *mtd = nand_to_mtd(chip);
+	int ret, i;
 
-	nand_release(&fun->chip);
+	ret = mtd_device_unregister(mtd);
+	WARN_ON(ret);
+	nand_cleanup(chip);
 	kfree(mtd->name);
 
 	for (i = 0; i < fun->mchip_count; i++) {