mtd: rawnand: ams-delta: Check mtd_device_register() return code

mtd_device_register() can fail, and when it does we should propagate
the error and cleanup what has been done before.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

drivers/mtd/nand/raw/ams-delta.c

@@ -283,10 +283,16 @@ static int ams_delta_init(struct platform_device *pdev)
 		goto err_unmap;
 
 	/* Register the partitions */
-	mtd_device_register(mtd, partition_info, ARRAY_SIZE(partition_info));
+	err = mtd_device_register(mtd, partition_info,
+				  ARRAY_SIZE(partition_info));
+	if (err)
+		goto err_nand_cleanup;
 
 	return 0;
 
+err_nand_cleanup:
+	nand_cleanup(this);
+
 err_unmap:
 	iounmap(io_base);