TDI: supported attributes set is not initialized by TDI parser (the query the cfrontend will get the zero value).

TDI parser needs to parsing the attributes field and populate the attributes_set correctly instead of using the class initialized the value (ENTRY_SCOPE = 0).
For the PortStat table,
      "supported_operations" : [],
      "attributes" : ["poll_intvl_ms"]
For the PortCfg table:
      "supported_operations" : [],
      "attributes" : ["port_status_notif_cb"]

