This change adds battery operating temperature check. Host and EC
will be turned off when overtemp. EC can be waked up by predefined
external signals like key press or AC_PRESENT gpio.
For safty reason, this change does not check battery temperature
after EC deep sleep.
Signed-off-by: Rong Chang <rongchang@chromium.org>
BUG=chrome-os-partner:8451,9108
TEST=none
Mock battery_temperature() fucntion to test.
Change-Id: I3203515b3df86192f690f9b98901020209ce49b3