Support multiple DcTracker for IWLAN refactoring

If the device is configured as AP-assited mode, multiple
DcTrackers will be created for each corresponding
data service. For legacy mode, only one DcTracker will
be created.

Test: Unit tests and telephony sanity tests
Bug: 73659459

Change-Id: I9f6afd65093dd1c65841466c6ff063717bb5bdaa