ENGR00274056-1 thermal: add device cooling for thermal driver

ENGR00274056-1 thermal: add device cooling for thermal driver

cpu cooling is not enough when temperature is
too hot, as some devices may contribute a lot of heat
to SOC, such as GPU, so we need to add device cooling
as well, when system is too hot, devices can also take
their actions to lower SOC temperature.

when temperature cross the passive trip, device cooling
driver will send out notification, those devices who
register this devfreq_cooling notification will take
actions to lower SOC temperature.

Signed-off-by: Anson Huang <b20788@freescale.com>