Integrity checking of NAS signalling messages in the MME bypass

[zmw12306]

https://github.com/srsran/srsRAN_4G/blob/fa56836b14dc6ad7ce0c3484a1944ebe2cdbe63b/srsepc/src/mme/s1ap_nas_transport.cc#L332-L336 According to TS 24301 4.4.4.3: All ESM messages are integrity protected except a PDN CONNECTIVITY REQUEST message if it is sent piggybacked in ATTACH REQUEST message and NAS security is not activated. Should integrity protection checking be applied here?