Added a patch for CMake to fix generating/building Bombermaaan with older SDL2/SDL2_mixer:
on Bullseye/Ubuntu 20.4, sdl2_mixer-config.cmake doesn't contain the target aliases in the SDL2_mixer namespace.
on Buster, sdl2-config.cmake doesn't contain the target aliases in the SDL2 namespace and the includes/libraries are not correctly added to the compilation and linkage options.
Added a patch for CMake to fix generating/building Bombermaaan with older SDL2/SDL2_mixer:
sdl2_mixer-config.cmake
doesn't contain the target aliases in theSDL2_mixer
namespace.sdl2-config.cmake
doesn't contain the target aliases in theSDL2
namespace and the includes/libraries are not correctly added to the compilation and linkage options.