event-loop.c: Use correct OS abstraction function for dupfd()

Signed-off-by: Philip Withnall <philip at tecnocode.co.uk>
Signed-off-by: Karsten Otto <ottoka at posteo.de>
Reviewed-by: David Fort <contact at hardening-consulting.com>
Reviewed-by: Marek Chalupa <mchqwerty@gmail.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

src/event-loop.c

@@ -134,7 +134,7 @@ wl_event_loop_add_fd(struct wl_event_loop *loop,
 		return NULL;
 
 	source->base.interface = &fd_source_interface;
-	source->base.fd = fcntl(fd, F_DUPFD_CLOEXEC, 0);
+	source->base.fd = wl_os_dupfd_cloexec(fd, 0);
 	source->func = func;
 	source->fd = fd;