Improve tone and audio mode logging in Telecom.

Add a local log to CallAudioModeStateMachine to log state changes and
audio mode changes which take place.
Add missing audio mode change logs for unfocused state.
Improve logging in InCallTonePlayer to make it more clear when tone
termination is going to trigger a mode change in CAMSM.

Test: Make calls and verify that the telecom dumpsys now logs the audio
mode state transitions, as well as audio mode changes.
Test: Inspect Telecom dumpsys logs for clarity of InCallTonePlayer logs.
Bug: 224688012

Change-Id: I4a1f264053d6557b54143c67d920aa5a12eaa075