spi/s3c64xx: Allow usage for ARCH_S3C24XX

Newer SoCs from the S3C24XX line, namely S3C2416/2443/2450 contain
hsspi-controllers compatible with the s3c64xx type.

The previous patches enabled platform support for it, so make the
driver also usable for the S3C24xx architecture.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>