Fix interfaces-config missing first-boot transaction after image upgrade

[rameshraghupathy]

Why I did it

On some image upgrade scenarios after sonic-installer install, interfaces-config.service can miss its initial boot transaction during first-boot platform package installation in rc.local. In this condition, the service remains inactive even after the system later recovers normally, leaving management interface eth0 unconfigured until interfaces-config.service is manually restarted.

This issue was observed after the Docker socket activation changes introduced by PR #25503, which can cause Docker and related services to be triggered earlier during first boot.

This change ensures interfaces-config.service is requeued after first-boot platform package installation completes so that management interface configuration succeeds automatically after image upgrade.

The change only affects the existing first-boot upgrade path in rc.local. Normal reboot flows are unchanged, and if interfaces-config.service has already completed successfully, the additional systemctl start operation is a no-op and does not impact existing platforms.

How I did it

Added the following recovery logic in rc.local after first-boot platform package installation:

systemctl reset-failed interfaces-config.service || true
systemctl start --no-block interfaces-config.service || true

How to verify it

nstall a new SONiC image using sonic-installer install
Reboot into the newly installed image

Verify that eth0 is configured automatically after first boot:

show ip int | grep eth0

Verify interfaces-config.service completed successfully:

systemctl status interfaces-config.service
Verify no manual recovery/restart is needed after image upgrade.

Which release branch to backport (provide reason below if selected)

• 202305
• 202311
• 202405
• 202411
• 202505
• 202511

Tested branch (Please provide the tested image version)

master

Description for the changelog

Fix first-boot image upgrade issue where interfaces-config.service could miss its initial startup transaction on SmartSwitch platforms, leaving eth0 unconfigured after upgrade.

[mssonicbld]

/azp run Azure.sonic-buildimage

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[rameshraghupathy]

@prabhataravind Please review

[mssonicbld]

This PR has backport request for branch(es): 202511.
Added label(s) for branch(es) 202511.

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