aaudio: keep track of streams using strong pointers

Maintain strong pointer to service stream during service calls.
Use simple AAudioStreamTracker instead of complex HandleTracker.

Bug: 65280854
Test: affects all MMAP streams, run all CTS tests, etcetera
Change-Id: I3d2ed8b588ea39c216dacd4dea503b11c33f36f3
25 files changed