Implement emergency radio in default HAL

Implemented adb shell command in default broadcast radio HAL to
simulate an emergency alert.

Bug: 361348719
Flag: EXEMPT HAL interface change
Test: adb root
Test: adb shell dumpsys android.hardware.broadcastradio.IBroadcastRadio/amfm --simulateAlert actual alert geo,transport future severe possible "alertmessage" en-US geocode:SAME,006109_geocode:SAME,006209_polygon:-38.47,-120.14,38.34,-119.95,38.52,-119.74,38.62,-119.89,-38.47,-120.14+geocode:SAME,006009
Change-Id: Idbfdb47a65c88bc3dc1839729b772bb285c563b4