Add mute state to the absolute volume callback

We need this information for the user to know whether the stream is
muted or not. With the absolute volume changes this is not reflected
with the index anymore

Test: atest AudioDeviceVolumeManagerTest
Bug: 391252779
Bug: 393657380
Flag: android.media.audio.unify_absolute_volume_management
Change-Id: I94ba9aafa50935d71c3b058e292f7b637927539b