Revert "cpufreq: interactive: Simplify frequency calculations"

This reverts commit 12eb52bcb246dd92b1e07725ce8778d62d557bc4.

We'll use this a bit smarter.

Change-Id: I0ca9f10f01720cc03de9b7084262ebf3a3a0e9e3
cpufreq: interactive: Support variable frequency calculations

Use a threshold value up to which we are evaluating the current
speed weighted by current load against each new choice of speed.
Above switch to the original frequency calculation proportional to
load relative to the max possible frequency which allows for more
dynamic and fair changes.

Default threshold is cpuinfo min which guarantees minimal freqs
and energy usage during (offloaded) media playback.

Also, choose the highest frequency below or at target, which
generally saves us one freq level.

Change-Id: Ic807cc89a6d5cfb47f353b0912ced489baae8cbf
Merge branch 'cm-11.0' into kk_mkt