ARM: EXYNOS4: Add support Core1 Power On/Off with hotplug in/out

To insert the code for power on/off with pmu control to support hotplug in/out core1
As for hotplug.c, the codes for core1 to be hotplug in/out is inserted.
As for regs-pmu.h, S5P_CORE_LOCAL_PWR_EN is defined.
As for platsmp.c, the codes for core1 to be powered on is inserted.

Signed-off-by: JungHi Min <junghi.min@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>