board: add support for the Arduino Nano Matter

[silabs-bozont]

Hey friends!
This PR adds support for the Nano Matter including:

• Basic platform, CoreAPI and flashing support
• GPIO
• PWM
• I2C/Wire
• SPI
• Bluetooth LE

All of these have been tested and confirmed to function, but feel free to do any additional testing!

ADC support is missing from the main Zephyr repo for the Nano Matter - I'm currently working on adding it. Once it's there I'll also include it here in a separate PR. Besides this the board has a pretty well rounded functionality.

OpenOCD 0.12.0-arduino1-static will have to be added to the package.json file - but I assume you keep that separately. This is needed for flasing the Nano Matter.

Please, let me know if you have any remarks and I'll fix them as soon as possible!

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[pillo79]

Thanks for mentioning the new required tool in the PR notes. Please add it to extra/artifacts/_common.json so that CI generates the correct files automatically.

[silabs-bozont]

@pillo79 Thanks for mentioning the new required tool in the PR notes. Please add it to extra/artifacts/_common.json so that CI generates the correct files automatically.

Thank you for the pointer, I've added it. Could you please check if it's correct?

[pillo79]

LGTM (not tested though). @silabs-bozont you should accept the CLA for us to use this in our repo though 😉 thanks!