This problem can be occurred in the following scenarios.
1. Run NFs(NRF/SCP/SMF/UPF/AUSF/UDM/PCF/BSF/NSSF/UDR) except AMF.
2. Run AMF
3. Run gNB/UE and try to register
4. STOP PCF
5. AMF Crashed
AMF discovered the PCF through SCP during the UE registration process.
At this time, ogs_sbi_nf_fsm_init() is not called,
so AMF does not have state information about PCF.
In other words, AMF state is NULL.
In such a situation, when PCF is terminated at this time,
a crash occurs as AMF attempts to change the PCF state.
So, I've fixed that state information is initialized to solve this problem.
e12b1be313