suppress warnings about easch <applet>_main() having

no preceding prototype

coreutils/od.c

@@ -156,6 +156,7 @@ static const char od_o2si[] = {
 	0xb, 1, 8, 9,
 };
 
+int od_main(int argc, char **argv);
 int od_main(int argc, char **argv)
 {
 	int ch;