ARM: S5PC100: Pre-requisite clock patch for plat-s5pc1xx to plat-s5p move

This is a pre-requisite clock patch for the plat-s5pc1xx to plat-s5p
movement. The patches that perform the movement of the code from
plat-s5pc1xx to plat-s5p (and mach-s5pc100) should also enable the
build for the mach-s5pc100/clock.c code.

Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>