[ARM] S3C2410: Move base clock code to plat-s3c24xx

Move the S3C2410 base clock list to arch/arm/plat-s3c24xx
as this code is common to the S3C2410, S3C2440 and S3C2442
cpus.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>