Tab5 audio, I2C improvements, UiDensity moved to lvgl-module and cleanup (#506)

- UiDensity moved to lvgl-module
- Deleted tt_hal and tt_hal_gpio (breaks apps, but will fix those right after merging)
- Added I2C 8 bit register operations
- Added device.properties to simulator
- Improved Tab5 hardware init, implement audio
- Add README.md to kernel

Modules/lvgl-module/source/module.c

@@ -60,6 +60,10 @@ bool lvgl_is_running() {
     return is_running;
 }
 
+enum UiDensity lvgl_get_ui_density(void) {
+    return TT_LVGL_UI_DENSITY;
+}
+
 struct Module lvgl_module = {
     .name = "lvgl",
     .start = start,