Goal

As a user, I want NIC slot based naming to work.

Naming scheme `rhel-9.5` (RHEL-44630 / https://github.com/redhat-plumbers/systemd-rhel9/pull/283) or `v250` are workaround that basically disable slot based naming in many cases.

When building appliances, changing NIC naming on upgrade breaks a lot of config and might require OOB access to fix.

-> backport https://github.com/systemd/systemd/pull/33682

Acceptance Criteria

• using `net.naming-scheme=rhel-9.x` I can enable `NAMING_FIRMWARE_NODE_SUN`
• on a Dell R6615 with R2A pcie riser and NICs in slot 1 & 2, the NICs are named `ens1*` and `ens2*`