bq27x00: Add new properties

This patch add support for reporting properties
POWER_SUPPLY_PROP_CHARGE_NOW, POWER_SUPPLY_PROP_CHARGE_FULL,
POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
POWER_SUPPLY_PROP_CHARGE_COUNTER, POWER_SUPPLY_PROP_ENERGY_NOW in
module bq27x00_battery.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Grazvydas Ignotas <notasas@gmail.com>