Add PixArt PAW-3222 mouse sensor driver

[ploopyco]

This PR implements a driver for the PixArt PAW-3222, which is a mid-tier mouse sensor.

Description

The PixArt PAW-3222 is a mid-tier mouse sensor with CPI up to 4,000 and up to 10g of acceleration.

During development, we were informed that many of the properties of the PAW-3222 are confidential, and we were required to sign an NDA with PixArt to develop the included sensor firmware. We have obtained a signed and executed release from confidentiality for the included sensor firmware, which can be uploaded here if requested. However, during our conversations with the QMK maintenance team, we were informed that the release wouldn't be necessary. Additionally, we were told that there were no explicit conflicts between this firmware and QMK's commitment to GPL.

The PAW-3222 is used in the upcoming Ploopy Nano 2 Trackball, which was used to test this implementation.

Types of Changes

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

Issues Fixed or Closed by This PR

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).

[tzarc]

Release waiver has been supplied and confirmed compatible with GPL2+.

[drashna]

Needs some docs, but otherwise LGTM

[ploopyco]

Documentation added.