Apply stream volume for the correct device

During music playback via headset, if sonification stream sounds,
sonification volume is limited to music volume in computeVolume().
However if application plays sonification stream continuously,
setStreamVolumeIndex can be called before previous sonification
sound stops.
This behavior leads unexpected volume settings then
sonification volume is not limited to music volume.
This fix sets the correct device which is not filtered by
Volume::getDeviceForVolume then avoid to update incorrect device volume.

Bug: 118098429
Test: Repeat alarm during music playback from headset

Change-Id: I92f9bd070dd9d5b7b523147e6c2ca1f233a53eb4