audio: Force select device whenever a stream on speaker_safe goes to standby

When speaker-safe device is enabled, all active usecases on
speaker will be re-routed to speaker-safe as we cannot have
co-existance of speaker and speaker-safe. However, the
outputs forced to speaker-safe are not moved back to speaker
when the output on speaker-safe finishes. Call select_devices
to force change to the previous devices, if required.

Bug: 64360927
Test: manual audio test
Change-Id: Icaa3b296088d789006e9eab4a73450aab94bfb1c