ANDROID: GKI: power: power-supply: Add POWER_SUPPLY_PROP_CHARGER_STATUS property

CHARGER_STATUS power-supply property reports the charger status.

Change-Id: I269b0be18b56d56c0ab0e68ee1d7194d09824dd6
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>
(cherry picked from commit c2427520)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 157994070
Signed-off-by: Will McVicker <willmcvicker@google.com>