fix: handle missing parsed_lldp in baremetal ports inspection hook

[RSabounds]

Handle a missing parsed_lldp key in the baremetal ports inspection hook so a node with no host-side LLDP skips gracefully instead of failing inspection.

Problem

InspectHookUpdateBaremetalPorts._parse_plugin_data accessed plugin_data["parsed_lldp"] (and ["all_interfaces"]) with hard key lookups. The parse-lldp hook only populates parsed_lldp when at least one interface reports usable LLDP TLVs. When a node returns no host-side LLDP, the key is absent and inspection fails:

Failed to inspect hardware. Reason: ... Unexpected exception KeyError during
processing for node: <uuid>. Error: 'parsed_lldp'

The __call__ method already handles the empty case (logs "No LLDP data" and returns), but _parse_plugin_data crashed on the missing key before that guard could run.

Change

• Read parsed_lldp and all_interfaces defensively with .get(...) or {}, so _parse_plugin_data returns an empty list and the existing "No LLDP data" guard handles the node instead of raising KeyError.
• Add tests for the missing-parsed_lldp and empty-parsed_lldp cases.

Context

A node can legitimately present no host-side LLDP (cabling/timing, a switch port down, or — as seen in the field — an Intel E810 NIC in Safe Mode whose firmware LLDP agent consumes inbound LLDPDUs before the host sees them). The E810 Safe Mode root cause is addressed separately by including the ice DDP in the IPA ramdisk (PUC-2035). This change is the defensive backstop so inspection degrades gracefully rather than crashing when LLDP is genuinely absent.

AMMO-1323