XDP/Mellanox: T7223: Fixed interfaces initialization

[zdc]

Change Summary

Fixed XDP and Mellanox interfaces initialization

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Other (please describe):

Related Task(s)

• https://vyos.dev/T7223

Related PR(s)

Proposed changes

For the XDP driver and Mellanox NIC, we create defunct_* interfaces to hide original interfaces from CLI, when they are replaced with VPP-enabled pairs. But sometimes IP addresses are not flushed from these defunct_* interfaces, which leads to broken routing afterward.

This commit introduces an additional flush operation for defunct_* interfaces to ensure that they do not conflict with VPP interfaces.

How to test

On a system with Mellanox card:

set interfaces ethernet eth1 address '192.0.2.1/24'
set vpp settings interface eth1 driver 'xdp'
commit

ip a show dev defunct_eth1

If you see an IP address on the interface, it was not flushed by ithe nterface initialization logic. This change fixes it.

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[sever-sever]

Flush addresses from renames defunct interface. This fixes connectivity issues due assignment addresses to defunct interface's