mtd: rawnand: mtk: Factorize out the logic cleaning mtk chips

There are some un-freed resources in one of the error path which would
benefit from a helper going through all the registered mtk chips one by
one and perform all the necessary cleanup. This is precisely what the
remove path does, so let's extract the logic in a helper.

There is no functional change.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Matthias Brugger <matthias.bgg@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20240826153019.67106-1-miquel.raynal@bootlin.com

drivers/mtd/nand/raw/mtk_nand.c

@@ -1429,6 +1429,23 @@ static int mtk_nfc_nand_chip_init(struct device *dev, struct mtk_nfc *nfc,
 	return 0;
 }
 
+static void mtk_nfc_nand_chips_cleanup(struct mtk_nfc *nfc)
+{
+	struct mtk_nfc_nand_chip *mtk_chip;
+	struct nand_chip *chip;
+	int ret;
+
+	while (!list_empty(&nfc->chips)) {
+		mtk_chip = list_first_entry(&nfc->chips,
+					    struct mtk_nfc_nand_chip, node);
+		chip = &mtk_chip->nand;
+		ret = mtd_device_unregister(nand_to_mtd(chip));
+		WARN_ON(ret);
+		nand_cleanup(chip);
+		list_del(&mtk_chip->node);
+	}
+}
+
 static int mtk_nfc_nand_chips_init(struct device *dev, struct mtk_nfc *nfc)
 {
 	struct device_node *np = dev->of_node;
@@ -1567,20 +1584,8 @@ static int mtk_nfc_probe(struct platform_device *pdev)
 static void mtk_nfc_remove(struct platform_device *pdev)
 {
 	struct mtk_nfc *nfc = platform_get_drvdata(pdev);
-	struct mtk_nfc_nand_chip *mtk_chip;
-	struct nand_chip *chip;
-	int ret;
-
-	while (!list_empty(&nfc->chips)) {
-		mtk_chip = list_first_entry(&nfc->chips,
-					    struct mtk_nfc_nand_chip, node);
-		chip = &mtk_chip->nand;
-		ret = mtd_device_unregister(nand_to_mtd(chip));
-		WARN_ON(ret);
-		nand_cleanup(chip);
-		list_del(&mtk_chip->node);
-	}
 
+	mtk_nfc_nand_chips_cleanup(nfc);
 	mtk_ecc_release(nfc->ecc);
 }