Fully re-implement the sound control section to fix laggy seekbars
KSM: bump-up max pages-to-scan from 200 to 512
CPUControl: add support and toggle for Snake Charmer
CPUControl: differenciate SnakeCharmer versions and disable switch under v1.2

The version 1.2 of Snake Charmer is used as a built-in kernel option and cannot (and shouldn't) be disabled.
IOTweaks: added controls for eMMC/SD-Card readahead & entropy contribution