Update SCO messaging pipeline.

The following things are moved from SatelliteController to
DatagramReciver:
- SatelliteDatagramListenerHandler: stores incoming datagrams in DB and
  deletes from DB after receiving ack.
- mDatagramReceiverAck
- registerForSatelliteDatagram
- unregisterForSatelliteDatagram
- pollPendingSatelliteDatagrams

The following things are moved from SatelliteController to
DatagramDispatcher:
- sendSatelliteDatagram: prioritizes sending emergency datagrams over
  non-emergency datagrams

The following methods are moved from SatelliteController to
SatelliteServiceUtils:
- getSatelliteError()
- getPhoneOrDefault()

Bug: 269637555
Test: atest SatelliteManagerTest, Basic sanity - flashed build on
cheetah-userdebug: making calls and sending sms is working
Change-Id: I919b2d603d71015d079a8ed2f61e7158b54cd89a