Improve code style for HIDL bcradio service

Improved code style for HIDL broadcast radio service by:
- marking classes as final if possible;
- fixing error prones;
- replacing Slog with Slogf
- replcacing HashMap and HashSet with ArrayMap and ArraySet;
- adding missing parameter names.

Bug: 258826042
Test: atest BroadcastRadioTests
Change-Id: I37fc29f734e2f5a162c927a44661640b3db525b5