rootdir: Remove cpufreq mode settings

 * AFAIK we no longer should have anything which depends on system
   server or settings writing to the cpufreq controls. Since new
   devices have their cpufreq config nodes nested per-cpu, this
   configuration is no longer valid. It also depends on sketchy
   kernel patches which only work when the moon is in the correct
   phase. Additionally, I see a lot of random logspam when
   devices are hotplugged.
 * If a device needs this functionality, a better way to do it
   is via a userspace daemon which is dedicated to the task since
   it can poll() on the various states and get notified in realtime.

Change-Id: Ib526663d760d6cb758e13f1fa29e7d6229de3daa