Revert "Revert "Enable voltage control via sysfs table""

good to go now

This reverts commit 4a10560e2185b0f47cffc09885480d208f35ea46

Change-Id: I90e5a0ba462a88fda1db39f19ca8788c755a6e1f
cpufreq: voltage control: fix derp

Needs more steps due to the CPU frequencies