aaudio loopback: improve latency tester

Add command line options.
Add magnitude measurement.
Add automated latency analyzer that uses round trip echo and an impulse correlation.
Uses Harmonic Product Spectrum technique but in the time domain.

Bug: 33398120
Bug: 38178592
Test: this is a test
Change-Id: Ied6c09e6d8d373a188c13ed85b27de6c4b7be2f4
Signed-off-by: Phil Burk <philburk@google.com>