Audioflinger dumpsys cleanup

Re-order audioflinger dumpsys and add argument parsing for various sections.

Additionally, to clean up:
- Pull out dumpsys conditional locking logic into utilities, which
  return guards
- Add utility to write strings to fd

Test: adb shell dumpsys media.audio_flinger with all combos
Test: Compiles/boots
Flag: EXEMPT logging only
Bug: 372070273
Change-Id: I8bcf467ee2792d90b298998267591a354e0661c3