hal: fix A2DP mute issue for compress playback

During A2DP suspending and resuming, there could be another
concurrency playback usecase which will restore device of
compress playback to a2dp as part of select_devices() called
in check_a2dp_restore.
Thus, when check_a2dp_restore is called again for compress
playback, unmute won't be applied as the out sound device
is already as a2dp.
Correct the logic to always check the unmute request during
check_a2dp_restore.

Change-Id: I87617d55b4d277f784c988180afa8f82af6c3f48