mtd: rawnand: ingenic: Make qi_lb60_ooblayout_ops static

Fix sparse warning:

drivers/mtd/nand/raw/ingenic/ingenic_nand_drv.c:105:32:
 warning: symbol 'qi_lb60_ooblayout_ops' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200410115121.11852-1-yuehaibing@huawei.com