WifiDiagnostics: Collect logs when detecting fatal firmware alert

When detecting fatal firmware alert, flushing HAL ring buffer to files

Bug: 114766171
Test: Manual test
Test: ./frameworks/opt/net/wifi/tests/wifitests/runtests.sh
Change-Id: I687efca90c25d8d9de224b6b2e426294cae1f0f1
4 files changed