spi: npcm-fiu: simplify the return expression of npcm_fiu_probe()

Simplify the return expression.

Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Link: https://lore.kernel.org/r/20200921131106.93228-1-miaoqinglang@huawei.com


Signed-off-by: Mark Brown <broonie@kernel.org>