suggest Mix_MusicInterface add type check

[baidwwy]

https://github.com/libsdl-org/SDL_mixer/blob/6845d9f3cb3f35542f1ec7e74dba6b30bf968959/src/mixer.c#L550

for example ~~music_type = detect_music_type(src);~~ interface->Checktype(src);

https://github.com/libsdl-org/SDL_mixer/issues/332

[baidwwy]

https://github.com/libsdl-org/SDL_mixer/blob/6845d9f3cb3f35542f1ec7e74dba6b30bf968959/src/mixer.c#L539 https://github.com/libsdl-org/SDL_mixer/blob/6845d9f3cb3f35542f1ec7e74dba6b30bf968959/src/mixer.c#L554

I want to add sndfile, but this check is blocking me

[slouken]

I think we want to just add the correct detection code to detect_music_type(), no?

[baidwwy]

https://github.com/libsdl-org/SDL_mixer/pull/499