Update Esp32 Ethernet for alternate clock modes

[AdrianSoundy]

Description

Adds an configuration option to select an alternate Phy Clock mode as used by the ESP32 Olimex POE series of devices.

Motivation and Context

Support issue on forum

How Has This Been Tested?

Fixed tested by andylyonette

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: adriansoundy adriansoundy@gmail.com

[nfbot]

Hi @AdrianSoundy,

I'm nanoFramework bot.
Thank you for your contribution!

A human will be reviewing it shortly. 😉