Fix missing define to map rgb_matrix function set to rgblight.

[ruddy17]

Necessary fix for rgb_matrix to work with via configurator.

Description

VIA configurator, a well known and convenient tool for changing settings and binds via generic HID protocol, allows to control rgblight QMK module. However, there is rgb_matrix - a separate LED module with more features and fancy effects. Right now a developer has to choose between having rgb_matrix and having VIA support. This PR aims to fix this.

In the core of QMK there is a list of defines that directly map rgb_matrix functions to rgblight ones (see rgb_matrix.h lines 152:192). The control interfaces of both rgblight and rgb_matrix are practically the same. The only function VIA uses that is not mapped is eeconfig_update_rgblight_current , and this PR fixes this.

Now VIA does not have a template for rgb_matrix, but we can use it's ability to extend an existing config and define our own effect list that matches rgb_matrix effects. Another catch is that VIA effect speed slider range is 0..3, while qmk expects 0..255. For the sake of cleanness of the code base I suggest that effect speed setting is disabled in VIA config (it is still adjustable by keycodes RGB_SPI and RGB_SPD). If VIA devs find time to work on this, a new option of "lighting":"qmk_rgb_matrix" parameter may be added, that incorporates necessary changes.

As a result of this fix one can set VIA_ENABLE = yes and RGB_MATRIX_ENABLE = WS2812 and expect it to succesfully compile and work as expected. It was tested thoroughly on a live device (geekboards macropad v2) with no problems observed. I am willing to help test this with any other board that supports via+rgblight.

Example of VIA config

Demo video

Types of Changes

• 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

• 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).

[fauxpark]

Thanks!

[fauxpark]

Wrong button...