Clean up headers, add todo.

stepmania/src/arch/ArchHooks/ArchHooks_darwin.cpp

@@ -130,6 +130,7 @@ void ArchHooks_darwin::DumpDebugInfo()
         vRam = 0;
     }
     
+    /* XXX update this information for G5s */
     /* Get processor */
     numProcessors = MPProcessorsScheduled();
     err = Gestalt(gestaltNativeCPUtype, &code);

stepmania/src/arch/ArchHooks/ArchHooks_darwin.h

@@ -10,9 +10,6 @@
  */
 
 #include "ArchHooks.h"
-#include <SDL.h>
-#include <SDL_thread.h>
-#include <queue>
 
 class ArchHooks_darwin : public ArchHooks
 {