Change ADNS9800 and PMW33XX SROM uploads to opt in.

[daskygit]

Description

Tested 3360, 3389 and ADNS9800 are functional without SROM upload.

I did get some odd behaviour with the ADNS9800 but my sensor has always seemed a little iffy.

I chose not to document the defines as the idea is to have a larger test base running no SROM uploads. Ultimately they'll be reworked so the SROM can be included in the users keymap or uploaded by other means.

Types of Changes

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

Issues Fixed or Closed by This PR

Checklist

• [x] My code follows the code style of this project: C, Python
• [x] 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.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [x] I have tested the changes and verified that they work and don't break anything (as well as I can manage).