pal: Use increase/decrease StreamUserCounter to protect getTimestamp

1) Pcm Offload write takes 80ms and held agm session obj lock for 80ms,
   and if getTimestamp comes during this period, it is blocked by
   agm session obj lock.
2) getTimestamp for all streams is protected by resourceManager lock
   and active stream lock.
3) Active stream lock will block LL get timestamp and writing.
4) LL underrun happened.

Fix it by using increase/decrease StreamUserCounter to protect getTimestamp

Change-Id: Ib985fe26f5ec34b0e8a739bb3984d4f78e69128c
1 file changed