Migrate audio permission provider prop listener

The java system property listener is non-functional. Migrate the native
permission provider to use a native system property change listener for
cache invalidation.

Add basic throttling to pushing updates following permission cache
invalidation, which delays the update after the sysprop changes and
conflates subsequent updates prior to the delay expiring.

Bug: 338089555
Test: Manual verification of listener responding to sysprop changes
Flag: com.android.media.audio.audioserver_permissions
Change-Id: Ib21120da5c01867ab9ee1ed019c912b307fda7da