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 4d5705ea6c
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.

keyboards/model01/rules.mk

@@ -59,4 +59,6 @@ MIDI_ENABLE = no            # MIDI support (+2400 to 4200, depending on config)
 UNICODE_ENABLE = no         # Unicode
 
 CUSTOM_MATRIX = yes
-CIE1931_CURVE = yes
+
+# You can set RGB_MATRIX_ENABLE = no in your rules.mk to disable this and save the Flash
+RGB_MATRIX_ENABLE = custom	# Enable RGB matrix effects (+10000).