Make sure of_device_id tables are NULL terminated.
Found by coccinelle spatch "misc/of_table.cocci"

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Greentime Hu <greentime@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>