Log Message:
SDL2_mixer: updated to 2.0.4

2.0.4:
* Removed smpeg support for mp3 music, now that it's replaced by libmpg123
* Fixed mp3 mad decoder to skip tags, which otherwise would lead to crashes
* Added support for Opus music playback using opusfile library

2.0.3:
* Fixed regression where Mix_Init() would return 0 for available music formats