[keyboard] mechwild/bb40

[lesshonor]

Description

Adds MechWild's bb40 to the main QMK repo.

The code has been publicly available for about six months, so I've added a LAYOUT alias to avoid breaking out-of-tree keymaps.

Types of Changes

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

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).

[github-actions]

Thank you for your contribution!
This pull request has been automatically marked as stale because it has not had activity in the last 45 days. It will be closed in 30 days if no further activity occurs. Please feel free to give a status update now, or re-open when it's ready.
For maintainers: Please label with bug, awaiting review, breaking_change, in progress, or on hold to prevent the issue from being re-flagged.

[lesshonor]

if someone could mark as awaiting review, that would be appreciated.

[drashna]

Only caveat here, is that weact now has a 8MHz crystal variant, too... But that doesn't effect this PR.

[lesshonor]

Forgot that I used the soon-to-be deprecated DEFAULT_FOLDER here, so I've removed it and added more explanatory text. (dunk2k W)

Haven't run into anyone flashing the wrong version in quite some time; while proving a negative is tough, maybe folks are reading the instructions more.