mtd: rawnand: diskonchip: Set the NAND_NO_BBM_QUIRK flag

We have a dummy block_bad() implementation returning 0. Let's set the
NAND_NO_BBM_QUIRK flag and let the core take care of that.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200511064917.6255-3-boris.brezillon@collabora.com