usb: pd: notify charger if source is PPS capable

The charger driver may need to perform different charging
behavior depending on whether the source is PPS capable or
not. This can be determined when evaluating the source
capabilities. If PPS capable, set PD_ACTIVE to 2. Use the
new enum definitions POWER_SUPPLY_PD_ACTIVE,
POWER_SUPPLY_PD_PPS_ACTIVE and POWER_SUPPLY_PD_INACTIVE
for better readability.

Change-Id: I2255fe404951e88a342095de21303358ae8ea50b
Signed-off-by: Jack Pham <jackp@codeaurora.org>