audio: Exported recommendedMuteDurationMs for output profiles

- Added muteDuration to customize mute duration while switching device's
path to avoid truncated sound at beginning.
- Muted duration will be replaced only when there are defined duration
in audio_policy_configuration.xml.

Bug: 183344508
Test: manual audio test with different audio_policy_configuration.xml,
which is with/without muteDuration definition.

Signed-off-by: Jasmine Cha <chajasmine@google.com>
Change-Id: Idced0e256a6b8e91ba2704c5ad89fbf8aba62bf5