Description of problem: Add FQDN option (39) to DHCPv6. This option can be used similarly to hostname (12) option in DHCPv4.
Patch posted u/s: https://patchwork.ozlabs.org/project/ovn/patch/20230602104341.245758-1-amusil@redhat.com/
ovn23.09 fast-datapath-rhel-9 clone created at https://bugzilla.redhat.com/show_bug.cgi?id=2224403
The clone covers version 23.09 already.