mtd: rawnand: sunxi: Fix the probe error path

nand_release() is supposed be called after MTD device registration.
Here, only nand_scan() happened, so use nand_cleanup() instead.

Fixes: 1fef62c1

 ("mtd: nand: add sunxi NAND flash controller support")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/linux-mtd/20200519130035.1883-54-miquel.raynal@bootlin.com