Add KSZ8041 as a supported PHY for the LPC17xx series

[Szalacinski]

Summary of changes

Adds the Microchip KSZ8041 PHY as a supported device for the LPC17xx series.

Impact of changes

Migration actions required

Documentation

None

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Pull request type

[] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[x] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[x] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

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[ciarmcom]

@Szalacinski, thank you for your changes.
@ARMmbed/mbed-os-ipcore @ARMmbed/mbed-os-maintainers please review.

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 1
Build artifacts

[0xc0170]

CI seems to be not executing tests, will report and investigate

cc @ARMmbed/mbed-os-test

[0xc0170]

All good, no execution of tests as this is target is not in the CI , thus skipped that stage.