cpufreq:LAB:dts:trats2: Add attributes necessary for correct LAB operation

cpufreq:LAB:dts:trats2: Add attributes necessary for correct LAB operation

Two extra attributes have been added. The "lab-num-of-states" describes how
many ranges will be used during LAB operation. Now the span of it equals to
20 (100 / 5).
The lab-ctrl-freq attribute maps number of idle CPUs and workload (from
scheduler) to LAB operations.

It is possible to specify exact freq (e.g. 1300000), enable boost
(e.g. 0xFFFFFFFF), set frequency to minimum (0xFFFFFFFE) or rely on
ONDEMAND governor to find suitable frequency.

Change-Id: I0ea6ffd8626aded5bed34166c59b9d34278feef2
Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>