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/build_html_examples.sh

@@ -6,12 +6,10 @@ rm -rf emscripten_builder
 git clone https://github.com/lvgl/lv_sim_emscripten.git emscripten_builder
 scripts/genexamplelist.sh > emscripten_builder/examplelist.c
 cd emscripten_builder
-git checkout 45e0bc5c8d3e55cfbcaf8214361d2335b8b9a7b4
 git submodule update --init -- lvgl
 cd lvgl
 git checkout $CURRENT_REF
 cd ..
-git submodule update --init -- lv_drivers
 mkdir cmbuild
 cd cmbuild
 emcmake cmake .. -DLVGL_CHOSEN_DEMO=lv_example_noop -DCMAKE_C_COMPILER_LAUNCHER=ccache -DCMAKE_CXX_COMPILER_LAUNCHER=ccache