Fix 1995/cdua under macOS

It took two things: get it to compile and then remove bad function
prototypes which were causing a segfault. It worked under linux and of
course it still does.

1995/cdua/Makefile

@@ -97,7 +97,7 @@ CDEFINE=
 
 # Include files that are needed to compile
 #
-CINCLUDE=
+CINCLUDE= -include stdlib.h -include stdio.h
 #CINCLUDE= -include stdlib.h
 #CINCLUDE= -include stdio.h
 #CINCLUDE= -include stdlib.h -include stdio.h