Reset stratum_notify flag on suspend_stratum as well.

util.c

@@ -1508,7 +1508,7 @@ void suspend_stratum(struct pool *pool)
 {
 	applog(LOG_INFO, "Closing socket for stratum pool %d", pool->pool_no);
 	mutex_lock(&pool->stratum_lock);
-	pool->stratum_active = false;
+	pool->stratum_active = pool->stratum_notify = false;
 	mutex_unlock(&pool->stratum_lock);
 	CLOSESOCKET(pool->sock);
 }