Allow 'system' user to modify cpufreq control files

This is needed by new CPU Settings in CMParts

Change-Id: I0ec4e0b1705670034a433df549b2895985c476af
init: provide initial pemissions for ondemand governor

also set all governor permissions a bit late

Change-Id: I5c1445b31bcaf34a535efd7438fd612ada460ea2
rootdir: Set permissions for additional interactive sysfs nodes

Change-Id: I2dbcdcc199c5f75d08e8ebf41cd6768c7648e27b