Access AudioPlaybackConfiguration players under mPlayerLock

Test: build and flash to Panther
Test: run cts-dev -m CtsMediaAudioTestCases  -t android.media.audio.cts.AudioPlaybackConfigurationTest
Bug: 247551216
Change-Id: I7bd9b61ad46ba2bf2395daad8257f9cd79c73159
(cherry picked from commit b89353ba)
Merged-In: I7bd9b61ad46ba2bf2395daad8257f9cd79c73159