Add svlinky converter

[sadekbaroudi]

Add the svlinky RP2040 to the converters so that existing projects can be converted. The svlinky board is open source and available at:
https://github.com/sadekbaroudi/svlinky

This converter is for the v0.2. The v0.1 is already compatible with the rp2040_ce converter. I had to change the pinout to allow the controller to be fully compliant with the vik specifications. The specification requires that the 2 extra gpio in the fpc connector are digital/analog. Given the RP2040 only has 4 analog capable pins, and all of them are used in the standard pinout on a pro micro controller, I had to take two of those out and swap them with different gpio, leading to this.

Description

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout (addition or update)
• Documentation

Issues Fixed or Closed by This PR

• N/A

Checklist

• My code follows the code style of this project: C, Python
• I have read the PR Checklist document and have made the appropriate changes.
• 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.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[zvecr]

Given the RP2040 only has 4 analog capable pins, and all of them are used in the standard pinout on a pro micro controller, I had to take two of those out and swap them with different gpio, leading to this.

Given this, I have some reservations around its compatibility. Though the general use of ADC+Converters is both less common and not automatic on some other drop in replacements.

Adding in a note to the docs (in ### svlinky section) might help somewhat, but i'm also sure it would be missed/ignored and users would build anyway and find out it didnt work once soldered.

[sadekbaroudi]

Given the RP2040 only has 4 analog capable pins, and all of them are used in the standard pinout on a pro micro controller, I had to take two of those out and swap them with different gpio, leading to this.

Given this, I have some reservations around its compatibility. Though the general use of ADC+Converters is both less common and not automatic on some other drop in replacements.

Adding in a note to the docs (in ### svlinky section) might help somewhat, but i'm also sure it would be missed/ignored and users would build anyway and find out it didnt work once soldered.

Hey @zvecr - I added a new commit to highlight for folks. I hope this alleviates some of your concern.