audiopolicy: avoid binder calls to system server with mutex held

Do not call mustAnonymizeBluetoothAddress() (which in turn uses binder
calls to system server (for permission checks...) with the audio policy
service mutex held. This can cause the system server binder queue to be
exhausted if other transactions to java AudioService are waiting on a
mutex held while calling into native audio policy service.

Bug: 303552947
Fixes: 329911862
Test: make
Change-Id: Id602be8600040077c7db26f1a9a0b8948ee1bc5c