nds32: add NULL entry to the end of_device_id array

Make sure of_device_id tables are NULL terminated.
Found by coccinelle spatch "misc/of_table.cocci"
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Acked-by: NGreentime Hu <greentime@andestech.com>
Signed-off-by: NGreentime Hu <greentime@andestech.com>

arch/nds32/kernel/atl2c.c

@@ -9,7 +9,8 @@
 
 void __iomem *atl2c_base;
 static const struct of_device_id atl2c_ids[] __initconst = {
-	{.compatible = "andestech,atl2c",}
+	{.compatible = "andestech,atl2c",},
+	{}
 };
 
 static int __init atl2c_of_init(void)