spi: uniphier: fix error return code in uniphier_spi_probe()

Fix to return negative error code -EPROBE_DEFER from the DMA probe defer
error handling case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20200429075855.104487-1-weiyongjun1@huawei.com


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