Update to LVGL 9.0.0 (#47)

- Updated LVGL from 8.3 to 9.0 (removed example/docs/demo folders)
- Updated esp_lvgl_port  to current status of the `lvgl9` branch on `esp-bsp`: https://github.com/espressif/esp-bsp/tree/lvgl9
- Updated all boards and drivers
- Removed `libs/lv_drivers` subproject as SDL is now supported by LVGL directly (although keyboard input seems broken)
- Updated `libs/lv_screenshot`
- Fixed the way `tt_statusbar` widget works due to behaviour change in LVGL
- Updated other lvgl code

libs/esp_lvgl_port/CHANGELOG.md

@@ -0,0 +1,32 @@
+# Changelog
+
+## 1.5.0
+
+### Features
+
+- Divided into files per feature
+- Added support for LVGL9
+
+## 1.4.0
+
+### Features
+
+- Added support for USB HID mouse/keyboard as an input device
+
+## 1.3.0
+
+### Features
+
+- Added low power interface
+
+## 1.2.0
+
+### Features
+
+- Added support for encoder (knob) as an input device
+
+## 1.1.0
+
+### Features
+
+- Added support for navigation buttons as an input device