ghost_hotplug: Decrease reschedule delay by 10 times

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
ghost_hotplug: Check only if current online cpus are equal to max/min cpus

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>
ghost_hotplug: Use a universal way to hotplug CPUs

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>