power: supply: act8945a_charger: Add status change update support

Add the charger status change interrupt support, it will report
the power supply changed event.

This interrupt is generated by one of the conditions as below:
 - the state machine jumps out of or into the EOC state
 - the CHGIN input voltage goes out of or into the valid range.
 - the battery temperature goes out of or into the valid range.
 - the PRECHARGE time-out occurs.
 - the total charge time-out occurs.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>