mtd: nand: gpmi: Fix gpmi_nand_init() error path

The GPMI driver is wrongly assuming that nand_release() can safely be
called on an uninitialized/unregistered NAND device.

Add a new err_nand_cleanup label in the error path and only execute if
nand_scan_tail() succeeded.

Note that we now call nand_cleanup() instead of nand_release()
(nand_release() is actually grouping the mtd_device_unregister() and
nand_cleanup() in one call) because there's no point in trying to
unregister a device that has never been registered.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Han Xu <han.xu@nxp.com>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>

drivers/mtd/nand/gpmi-nand/gpmi-nand.c

@@ -2055,18 +2055,20 @@ static int gpmi_nand_init(struct gpmi_nand_data *this)
 
 	ret = nand_boot_init(this);
 	if (ret)
-		goto err_out;
+		goto err_nand_cleanup;
 	ret = chip->scan_bbt(mtd);
 	if (ret)
-		goto err_out;
+		goto err_nand_cleanup;
 
 	ret = mtd_device_register(mtd, NULL, 0);
 	if (ret)
-		goto err_out;
+		goto err_nand_cleanup;
 	return 0;
 
+err_nand_cleanup:
+	nand_cleanup(chip);
 err_out:
-	gpmi_nand_exit(this);
+	gpmi_free_dma_buffer(this);
 	return ret;
 }