init [1/4]: set permissions on governors sysfs nodes

1. interactive
2. ondemand
3. assume smp uses shared cpufreq policy for all CPUs

also, set permission for boostpulse
it will fix some permission issues like:

E/S5PC110 PowerHAL(  482): Error writing to boostpulse: No such device
E/S5PC110 PowerHAL(  482): Error opening interactive boostpulse interface: Permission denied
E/S5PC110 PowerHAL(  495): Error opening /sys/devices/system/cpu/cpufreq/interactive/timer_rate: Permission denied

Signed-off-by: Humberto Borba <humberos@gmail.com>
Change-Id: I581aaa1daf2ba5911e89398a4f8a1567fd6569c9

Conflicts:
	prebuilt/etc/init.local.rc