move setgroups definition to libbb.h so that it no longer inadvertently
get hidden attribute
diff --git a/include/libbb.h b/include/libbb.h
index f50ae36..0d6e3af 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -79,9 +79,11 @@
# endif
#endif
-/* Some libc's forget to declare these, help them */
+/* Some libc's forget to declare these, do it ourself */
extern char **environ;
+/* Set the group set for the current user to GROUPS (N of them). */
+int setgroups(size_t n, const gid_t *groups);
#if defined(__GLIBC__) && __GLIBC__ < 2
int vdprintf(int d, const char *format, va_list ap);
#endif