power: charger: change charger detection for TA plug in

There is a problem when is_active_chg_plugged_in API check active_chg_plugged_in
with active_path for TA in unplug_check_worker. So we used the_chip->usb_present
for TA detection correctly due to the same usb port.(USB_IN->USB_OUT->DC_IN->DC_OUT).

Change-Id: If51923ba12e6496bf63123104a158d34cad377b0