disabling the discovery of SDL13+ on desktop. SDL13 has become SDL2 with a completely different ABI and will require a new FindSDL2 module for Cmake to be found; for current sdl development installations, hedgewars will either use the compatibility layer (present in sdl1.3 but not in sdl2) or just fail to build (in case sdl2 is installed but sdl1.2.* is not). whew

LIBRARY "openalbridge"
EXPORTS
	openal_init
	openal_close
	openal_ready
	openal_loadfile
	openal_playsound	
	openal_pausesound
	openal_stopsound
	openal_playsound_loop
	openal_stopsound_free
	openal_freesound
	openal_toggleloop
	openal_setvolume
	openal_setglobalvolume
	openal_togglemute
	openal_fade
	openal_fadein
	openal_fadeout