aaudio example: fix loopback test

Support both I16 and FLOAT format.
Silence output at beginning when skipping buffers. Was sometimes spewing noise.
Print more information when it fails so we can debug the failure.
Fix getting framesPerBurst from wrong stream.
Track when read gets too few frames.

Bug: 38268031
Bug: 78139448
Test: this is a test
Change-Id: If562856ab2eac607a8bb15da1cc587ae631f7a1d