spi: s3c64xx: Use the managed spi master allocation function

Use devm_spi_alloc_master() and get rid of one goto error path

Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20230606012051.2139333-2-andi.shyti@kernel.org


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