mm: Revert mm subsystem back to 3.0.31 kernel version to work around camera issues

credits to Googy for the basis work
boeffla_defconfig: Disable MHL support to prevent freezing when using dock
cpufreq: 1700MHz CPU OC
Revert "boeffla_defconfig: Support hot plugging for legacy governors"

This reverts commit e5cb706c07451ec808a1a776b48f952e2fa39874.
Release tag: 2.3-beta3