SDL: Silence a large number of compile warnings (WIP)

There are some real bugs in here, but we're drowning in warnings.

Change-Id: I7c2c0eafc8426327521bdd8a3ac2d3742ac16864

apps/plugins/sdl/progs/wolf3d/id_us.h

@@ -96,6 +96,6 @@ void	        USL_PrintInCenter(const char *s,Rect r);
 char 	        *USL_GiveSaveName(word game);
 
 void            US_InitRndT(int randomize);
-int             US_RndT();
+int             US_RndT(void);
 
 #endif