[DS] Call cannot call out from Car kit

The original code can not work since the subscription is wrong.
So BT can not correctly get the service / signal strength and update
to remote device. Thus some IOT issue happened.

Using the new interface to correctly register.

Change-Id: I2976eb12e44f78d896a04ef01a1a6ebb848f62f0

Conflicts:
	src/com/android/bluetooth/hfp/HeadsetPhoneState.java