ARM: S3C64XX: use timekeeping wrapper on cpuidle
ARM: S3C64XX: use timekeeping wrapper on cpuidle

The timekeeping is computed from the cpuidle core if we set
the .en_core_tk_irqen flag. Let's use it and remove the duplicated
code.

Signed-off-by: Daniel Lezcano <e9fa45941f2ebe89c1b9d6c5f339ab42eadb8567@linaro.org>
Tested-by: Mark Brown <b51b9a92386687a9ac927cebfa0f978adeb8cea5@opensource.wolfsonmicro.com>
Signed-off-by: Kukjin Kim <3fc711f4e08bc570a586748633ff7c76d0e1e253@samsung.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs