Associate node id based on node id type

We always create PFCP association with node_id type FQDN in case of UPF registered with NRF. Which is not wrong as we can have fqdn, ipv4 address, ipv6 address in the NF profile with 3! possibilities. Also we can not know PFCP node id type in advance before association setup.

https://gitlab.eurecom.fr/oai/cn5g/oai-cn5g-smf/-/blob/master/src/smf_app/smf_app.cpp#L1428

• Snippet from 29.510, Table 6.1.6.2.2-1: Definition of type NFProfile

We also maintain pending_associations with node id type FQDN till we get association response and nf profile association gets failed if we have node id type ipv4 address from UPF (e.g. SD-Fabric UPF).

https://gitlab.eurecom.fr/oai/cn5g/oai-cn5g-smf/-/blob/develop/src/smf_app/smf_pfcp_association.cpp#L531

UPF can have either FQDN or IPv4/IPv6 address type for node id of the UPF

• Snippet from 29.244

We address this issue by checking both fqdn and ip address while asociating upf profile.