audioclient: Release a recorder when AudioRecord dies

When AudioRecord object is destroyed, it must unregister
with AudioManager so it removes the tracker from
the tracking list.

Bug: 123312504
Test: start and stop audio recording, check "dumpsys audio"
Change-Id: Ida71512cb811d7602da349a58a91c95111078ef4

media/libaudioclient/RecordingActivityTracker.cpp

@@ -36,6 +36,9 @@ RecordingActivityTracker::RecordingActivityTracker()
 
 RecordingActivityTracker::~RecordingActivityTracker()
 {
+    if (mRIId != RECORD_RIID_INVALID && mAudioManager) {
+        mAudioManager->releaseRecorder(mRIId);
+    }
 }
 
 audio_unique_id_t RecordingActivityTracker::getRiid()