SoundPool: Add clang-tidy and fix

Test: soundpool_stress
Test: SoundPoolAacTest
Test: SoundPoolHapticTest
Test: SoundPoolMidiTest
Test: SoundPoolOggTest
Bug: 157501605
Change-Id: I7bba857a8b44b6255d423086127da0e2df4ce1c4
11 files changed