`SDL_RWops_renamed_SDL_IOStream` with latest SDL3 commit

[Semphriss]

This is probably known already, I'm opening this just to keep track of the progress and so that other people know it's a known issue.

Compiling SDL and SDL_img from source reports a very long list of errors related to SDL_RWops being renamed to SDL_IOStream.

Same issue with SDL_ttf - I did not check other satellite libraries (SDL_net etc.)