spi: s3c24xx: Switch to use devm_spi_alloc_master()

Switch to use devm_spi_alloc_master() to simpify error path.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220920142216.3002291-1-yangyingliang@huawei.com


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