Poll on HUP rather than OUT to detect worker process failure,

this works better with Solaris

bin/varnishtest/vtc_varnish.c

@@ -304,7 +304,7 @@ varnish_launch(struct varnish *v)
 	fd[0].fd = v->cli_fd;
 	fd[0].events = POLLIN;
 	fd[1].fd = v->fds[0];
-	fd[1].events = POLLOUT;
+	fd[1].events = POLLHUP;
 	i = poll(fd, 2, 10000);
 	vtc_log(v->vl, 4, "CLIPOLL %d 0x%x 0x%x",
 	    i, fd[0].revents, fd[1].revents);