cpufreq_conservative: Improve support for micro idle accounting

The minimum samplerate calculations of the current conservative
implementation assume that there is not micro idle accounting present,
however, we do have that capability in our idle estimates.  As a result,
we can support lower polling intervals just like ondemand does.

Signed-off-by: Andrew Dodd <atd7@cornell.edu>

Change-Id: I183d494a74a99d4c662554895f9eb6d9f4092162
cpufreq: conservative: Set some usable defaults

Change-Id: I0afd7a69c5cafde2ba5a6502a4cf4f0c4b070c48
flo: Enable conservative and disable userspace governor

Signed-off-by: Zhao Wei Liew <zhaoweiliew@gmail.com>