In some bootloader, IRQ is enabled. Writing nand triggers unexpected
interrupts. So disable nand irq in initialization. After nand
initialized and in working state, irq is controlled by nand driver.
Signed-off-by: NHaojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: NEric Miao <eric.y.miao@gmail.com>