ARM: S3C24XX: Move mach-s3c2412/ cpufreq driver into mach-s3c24xx/

This patch moves mach-s3c2412/cpufreq driver into mach-s3c24xx/
and removes arch/arm/mach-s3c2412/ directory in kernel.

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>