Clear binder identity in callback of IMS IPC interfaces

The binder identity does get cleared when goes from client process
into phone process. When it comes back from phone to client, the
binder identity should also be cleared.

Bug: 193923945
Test: atest android.telephony.cts.TelephonyManagerTest
Test: atest ImsServiceTest RcsFeatureControllerTest ImsMmTelManagerTest
Change-Id: I34225e32111879e155c9f7865f0045430d171467