add kinT kinesis keyboard controller (kint41 variant)

[stapelberg]

Description

This adds the kint41 variant of the https://github.com/kinx-project/kint kinesis keyboard controller.

We already have kint2pp and kint36 in QMK, so this PR completes the currently supported Teensy options :)

Types of Changes

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

Issues Fixed or Closed by This PR

• fixes Teensy 4.1 (kint41) QMK support kinx-project/kint#5

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).

[stapelberg]

Friendly ping on this one?