Return positive for cnx_needed when no_work is true.

cgminer.c

@@ -4999,6 +4999,9 @@ static bool cnx_needed(struct pool *pool)
 		return true;
 	if (pool_unworkable(cp))
 		return true;
+	/* We've run out of work, bring anything back to life. */
+	if (no_work)
+		return true;
 	return false;
 }