Use Phone.getState() to check for active call to skip data stall recovery

The existing flag mInVoiceCall in DcTracker has instance of CS calls
only and it works for specific use cases. However for skipping data
stall we would need to check any type of calls to avoid call drops.

Bug: 141207103
Test: Manually verified by making VoLTE call
      atest frameworks/opt/telephony/tests/telephonytests/
Change-Id: I5e28ddce41ff0597e7d650b53cae2762c99bc8b3