audio policy: disable silencing of background UID record

There is a problem when audioserver process restarts where we fail to
reload the list of active UIDs causing silent capture for all apps
until they are restarted.

Bug: 77300296
Bug: 63938985
Test: crash audioserver and check that capture still works.
Change-Id: Ie1a93c496516c1b7208780949054832a8a073044