Update ringer setting API visibility per council feeedback

- Remove MANUAL_RINGER_TOGGLE_COUNT from SystemAPI
- Make VOLUME_HUSH_* SystemAPI to align with VOLUME_HUSH_GESTURE

Bug: 113323148
Test: make update-api
Change-Id: I19b9cbfb0489889b4747e1102566c3a8cb60817f
2 files changed