[Core] Refactor OLED to allow easy addition of other types (#13454)

* add docs

* core changes

* update keyboards to new OLED

* updated users to new OLED

* update layouts to new OLED

* fixup docs

* drashna's suggestion

* fix up docs

* new keyboards with oled

* core split changes

* remaining keyboard files

* Fix The Helix keyboards oled options

* reflect develop

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: mtei <2170248+mtei@users.noreply.github.com>

keyboards/boardsource/microdox/keymaps/via/keymap.c

@@ -46,7 +46,7 @@ const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
 )
 };
 
-#ifdef OLED_DRIVER_ENABLE
+#ifdef OLED_ENABLE
 oled_rotation_t oled_init_user(oled_rotation_t rotation) {
   if (is_keyboard_master())
     return OLED_ROTATION_180;

keyboards/boardsource/microdox/keymaps/via/rules.mk

@@ -1,4 +1,5 @@
-OLED_DRIVER_ENABLE = yes
+OLED_ENABLE = yes
+OLED_DRIVER = SSD1306
 VIA_ENABLE = yes
 EXTRAKEY_ENABLE = yes
 RGBLIGHT_ENABLE = yes