Remove unused EEPROM stuff.

[tzarc]

Description

There's been some churn in QMK w.r.t. emulated EEPROM and the like -- let's just get base support into QMK first and we can address other things under other PRs.

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).

[dexter93]

reopening for reference. rebase and rework will follow