Display Nexus FEX as a separate device on the topology map

NetBrain currently displays a Cisco Nexus switch and its attached Fabric Extender (FEX) as a single combined unit on the map, even though the FEX may be physically installed in a separate rack from the parent switch. This enhancement would allow the FEX to be rendered as a distinct device object on the map, separate from its parent Nexus switch, while preserving the logical association between them. Providing this level of granularity would give customers accurate physical topology representation, improving documentation and troubleshooting for environments where FEX units are not co-located with their parent switch.