aaudio test: improve stealing test

Use class and locks to eliminate race condition.
Add -dDelay to sleep before open.
Add -rRetries to set maximum retries when reopening
after a disconnect.

Bug: 157777324
Test: adb shell test_steal_exclusive -r1 -d0
Change-Id: I847c57c3dc0d5d52bb2d03f1e85ebc13216ee41d