Fix rc-update, #187487 and release rc2.

src/builtins.h

@@ -12,6 +12,7 @@ int fstabinfo (int argc, char **argv);
 int mountinfo (int argc, char **argv);
 int rc_depend (int argc, char **argv);
 int rc_status (int argc, char **argv);
+int rc_update (int argc, char **argv);
 int runscript (int argc, char **argv);
 int start_stop_daemon (int argc, char **argv);