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/lvgl/scripts/cppcheck_run.sh

@@ -1 +1,3 @@
+#!/bin/sh
+
 cppcheck -j8 --template="{severity}\t{file}:{line}\t{id}: {message}" --enable=all ../src/ --output-file=cppcheck_res.txt --suppress=unusedFunction --suppress=preprocessorErrorDirective --force