[ARM] 3637/1: S3C24XX: Add mpll clock, and set as fclk parent

Patch from Ben Dooks

Update the clocks with the MPLL clock, and
use it as the parent. Also export these to
the rest of arch/arm/mach-s3c2410

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>