Segfault in HSPOST control command

A segfault occurs in the HSPOST command if node->rs->is_hs_dir is checked but the router_status entry for the node does not exist. I have a fix for this issue on my Github - https://github.com/DonnchaC/tor/commit/27f006bcad4a1a27339130ffb09637f4baaf7dbe

    if (!node->rs->is_hs_dir) {
      connection_printf_to_buf(conn, "552 Server \"%s\" is not a HSDir"
                                     "\r\n", server);
      goto done;
    }