AudioTrack: Fix extended timestamp offset

The extended timestamp server and kernel location positions
need the proper client side delta offset for native AudioTrack API calls.
The client location position is unaffected along with the legacy timestamp.

Test: test_timestamp, Photos, kill audioserver
Bug: 65386236
Change-Id: Idd71b6a31e0e86a323d0e5e343a2836e34c08673