T7887: system_option: Add validation for memory hugepage-count

[natali-rs1985]

Change summary

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)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://vyos.dev/T7887

Related PR(s)

How to test / Smoketest result

vyos@vyos:~$ python3 /usr/libexec/vyos/tests/smoke/cli/test_system_option.py
test_ctrl_alt_delete (__main__.TestSystemOption.test_ctrl_alt_delete) ... ok
test_kernel_options (__main__.TestSystemOption.test_kernel_options) ... ok
test_performance (__main__.TestSystemOption.test_performance) ... ok
test_reboot_on_panic (__main__.TestSystemOption.test_reboot_on_panic) ... ok
test_ssh_client_options (__main__.TestSystemOption.test_ssh_client_options) ... ok

----------------------------------------------------------------------
Ran 5 tests in 52.839s

OK

Checklist:

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

[github-actions]

👍
No issues in PR Title / Commit Title

[Copilot]

Pull Request Overview

Adds validation to ensure configured hugepage memory does not exceed available system memory and refactors duplicated hugepage size aggregation logic into a helper. Updates smoketest configurations to align with the new validation logic.

• Introduces _get_total_hugepages_and_memory helper to remove duplicated logic.
• Adds hugepage memory availability validation in verify().
• Adjusts test configs to lower hugepage-count values.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/conf_mode/system_option.py	Adds hugepage aggregation helper and validation logic; refactors apply() to reuse helper.
smoketest/configs/vpp	Updates hugepage-count to fit new validation constraints.
smoketest/config-tests/vpp	Updates hugepage-count in test setup to align with validation.

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

---

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[github-actions]

CI integration 👍 passed!

Details

CI logs

• CLI Smoketests (no interfaces) 👍 passed
• CLI Smoketests VPP 👍 passed
• CLI Smoketests (interfaces only) 👍 passed
• Config tests 👍 passed
• Config tests VPP 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed

[zdc]

The code looks fine to me.
I have not tested it.

[dmbaturin]

It looks sensible, so I think it's a good time to start testing it.