Adding dual ethernet 316 dev-kit

[humphrey-xmos]

Adding support for new dual ethernet dev-kit. BUT, only first PHY for now. For reference these changes are built in lib_ethernet PR, xmos/lib_ethernet#182

Documentation update to follow this PR.

Please note, to complete port will need the following tasks to be completed on lib_ethernet,

• RMII 8b tx lib_ethernet#85
• RMII dual port implementation lib_ethernet#91

Plus, updates to dual ethernet test board driver to fix issue of trying to access vendor specific register (0x302) without using MMD function. Added defines for magic numbers.
Also, added debug units to ethernet boards, for selective debug output.

[Copilot]

Pull Request Overview

This PR adds support for the new dual ethernet XK-ETH-316-DUAL development kit, implementing only the first PHY (ETH0) for now. The changes include board configuration files, PHY driver implementation, and necessary updates to version numbers and documentation.

Key changes:

• Addition of XK-ETH-316-DUAL board support with single PHY implementation
• Debug unit additions for selective debug output across ethernet boards
• Version bump from 1.3.0 to 1.4.0 across all configuration files

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
xn_files/xk-eth-316-dual.xn	New board configuration file defining ports and hardware layout for dual ethernet dev-kit
lib_board_support/src/boards/xk_eth_316_dual/xk_eth_316_dual.xc	New PHY driver implementation for DP83825I PHYs with MMD register access
lib_board_support/api/boards/xk_eth_316_dual/board.h	New API header defining board-specific functions and constants
lib_board_support/src/boards/xk_eth_xu316_dual_100m/xk_eth_xu316_dual_100m.xc	Code improvements including debug units, magic number defines, and MMD register fixes
settings.yml, module_build_info, lib_build_info.cmake	Version updates from 1.3.0 to 1.4.0
lib_board_support/api/boards/boards_utils.h	Board enumeration updates to include new XK_ETH_316_DUAL

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[shuchitak]

Looks great! Hopefully we'll get more confidence that it works when we run lib_ethernet HW tests on this board.