suppress warnings about easch <applet>_main() having

no preceding prototype

coreutils/false.c

@@ -13,6 +13,7 @@
 #include <stdlib.h>
 #include "busybox.h"
 
+int false_main(int ATTRIBUTE_UNUSED argc, char ATTRIBUTE_UNUSED **argv);
 int false_main(int ATTRIBUTE_UNUSED argc, char ATTRIBUTE_UNUSED **argv)
 {
 	return EXIT_FAILURE;