spi/s3c64xx: Convert to devm_request_and_ioremap()

Saves some error handling and a small amount of code.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>