[keyboard] add jacky_studio/piggy60/rev2

[lesshonor]

Description

Previously:

• [jacky_studio/piggy60] warn about incompatible PCB rev #20232
• [jacky_studio/piggy60] move AVR PCB under rev1 #20253

This PR trilogy has a predictable conclusion.

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).