NAND ECC modes (or providers) have their own enumeration but, unlike
their algorithms counterpart, there is no invalid or uninitialized
value to discriminate between an error and having chosen a no-ECC
situation. Add an "invalid" entry for this purpose.
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200526195633.11543-7-miquel.raynal@bootlin.com