feat(shields): Add elephant42 Shield Support (#1009)

* Initial Elephant42 implementation

* Add underglow feature

* Fix keymap

* Copy corne defconfig for OLED and LED

* Fix matrix positions

* Add nice_nano_v2.overlay

* Usability improvements to keymap

* Update LED length

* Delete nice_nano v1 overlay

* Remove unused conf files

* Add copyright/license headers

* PR feedback

* Try fixing formatting again

* Minor format

* More missed tabs

* Format

app/boards/shields/elephant42/Kconfig.defconfig

@@ -0,0 +1,55 @@
+# Copyright (c) 2021 The ZMK Contributors
+# SPDX-License-Identifier: MIT
+
+if SHIELD_ELEPHANT42_LEFT
+
+config ZMK_KEYBOARD_NAME
+    default "Elephant42"
+
+config ZMK_SPLIT_BLE_ROLE_CENTRAL
+    default y
+
+endif
+
+if SHIELD_ELEPHANT42_LEFT || SHIELD_ELEPHANT42_RIGHT
+
+config ZMK_SPLIT
+	default y
+ 
+if ZMK_DISPLAY
+
+config I2C
+	default y
+
+config SSD1306
+	default y
+
+config SSD1306_REVERSE_MODE
+	default y
+
+endif # ZMK_DISPLAY
+
+if LVGL
+
+config LVGL_HOR_RES_MAX
+	default 128
+
+config LVGL_VER_RES_MAX
+	default 32
+
+config LVGL_VDB_SIZE
+	default 64
+
+config LVGL_DPI
+	default 148
+
+config LVGL_BITS_PER_PIXEL
+	default 1
+
+choice LVGL_COLOR_DEPTH
+	default LVGL_COLOR_DEPTH_1
+endchoice
+
+endif # LVGL
+
+endif