The current preprocessor logic prevents CONFIG_OF_PRIOR_STAGE from being
used in U-Boot SPL. Change the logic to also make it available in U-Boot
SPL.
Signed-off-by: NLukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>
Tested-by: NBin Meng <bmeng.cn@gmail.com>
Reviewed-by: NAnup Patel <anup.patel@wdc.com>