Handle remote exception for bcradio openSession

Added logic to return null when AIDL broadcast radio HAL client opens
a session, but broadcast radio HAL throws remote exception during
setting tuner callback.

Bug: 358467578
Flag: EXEMPT bugfix
Test: atest com.android.server.broadcastradio.aidl.TunerSessionTest
Change-Id: I1886bb3fbbd5a46b29761a7deba334bae4dca3c0