mtd: rawnand: omap2: Fix check 0 for platform_get_irq()

Refer to commit a85a6c86 ("driver core: platform: Clarify that IRQ
0 is invalid"). Do not check 0 for platform_get_irq(), because
platform_get_irq() never return zero, and use the return error code of
platform_get_irq() instead of -ENODEV.

Signed-off-by: Yi Yang <yiyang13@huawei.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20230821084622.218442-1-yiyang13@huawei.com