doom64ex cmake patch

Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt  (revision 1094)
+++ CMakeLists.txt  (working copy)
@@ -125,4 +125,8 @@
    Ext/ChocolateDoom/net_structrw.c
 )

-target_link_libraries(doom64ex ${PNG_LIBRARY} ${SDL_LIBRARY} ${FLUIDSYNTH_LIBRARIES} ${SDLNET_LIBRARY} ${OPENGL_LIBRARY})
+IF(UNIX)
+   target_link_libraries(doom64ex ${PNG_LIBRARY} ${SDL_LIBRARY} ${FLUIDSYNTH_LIBRARIES} ${SDLNET_LIBRARY} ${OPENGL_LIBRARY} m dl)
+ELSEIF(UNIX)
+   target_link_libraries(doom64ex ${PNG_LIBRARY} ${SDL_LIBRARY} ${FLUIDSYNTH_LIBRARIES} ${SDLNET_LIBRARY} ${OPENGL_LIBRARY})
+ENDIF(UNIX)