RESTRICT AUTOMERGE: aaudio: improve test_atomic_fifo

Check for the effects of setting a bogus counter.
Check for writes to memory surrounding the FIFO.
Check for negative array indices.

Bug: 120789744
Test: this is a test
Change-Id: Ia30cdef7f9d60f0a98b9af964cb3b3159df37dc9
(cherry picked from commit 31a8d440)