files: Close ctl tty via generic engine

Just mark the fle as "fake" and the engine will do all the work.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

criu/files.c

@@ -854,7 +854,7 @@ int prepare_ctl_tty(int pid, struct rst_info *rst_info, u32 ctl_tty_id)
 	e->fd		= reserve_service_fd(CTL_TTY_OFF);
 	e->type		= FD_TYPES__TTY;
 
-	if (collect_fd(pid, e, rst_info, false)) {
+	if (collect_fd(pid, e, rst_info, true)) {
 		xfree(e);
 		return -1;
 	}

criu/tty.c

@@ -733,7 +733,6 @@ out:
 	close(slave);
 err:
 	pty_free_fake_reg(&fake);
-	close(fd);
 	return ret ? -1 : 0;
 }