ARM: EXYNOS4: Fix wrong constants in the hotplug assembly code.

This patch fixes wrong constants in the hotplug assembly code for
Exynos4 such as Russell's changing in vexpress hotplug and fixes
hard-coded control register constatns also.

Reported-by: Changhwan Youn <chaos.youn@samsung.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>