Modified AudioService to broadcast ACTION_MICROPHONE_MUTE_CHANGE intent

to all users

Before this change, ACTION_MICROPHONE_MUTE_CHANGED was broadcasting only
to system user. This causes CTS test, AudioManagerTest#testMicrophoneMuteIntent to fail when
the device is running on secondary user. This change modifies the
broadcast to all users.

Bug: 134509101
Test: make, flash local, then atest android.media.cts.AudioManagerTest#testMicrophoneMuteIntent
Change-Id: Idaf46782429dd4f3094fc5f6eb92da1a3e811b7b