Keyboard: keyboardio model01: rgbmatrix support (#3989)

Keyboard: keyboardio model01: rgbmatrix support (#3989)

* model01: implement RGB matrix feature

LEDs can still be individually controlled if this is switched off.

* model01: use fast banked LED setting commands

* model01: update default keymap to use RGB matrix

* model01: update RGB matrix support to match common_features.mk

* rgb_matrix: include <string.h>

This was missing after commit 4d5705ea6ceeb11cd2adc018644ec87c51af4e86
which introduces a use of memset().

* model01: make g_rgb_leds weak

This allows users to override which LEDs are configured as
modifiers, or tweak the x/y coordinates, should they so choose.