Created Drivers folder with ILI934x subproject (#209)

Refactored all existing boards to re-use the ILI934x driver code.

Boards/Simulator/Source/LvglTask.cpp

@@ -17,6 +17,8 @@ static uint32_t task_max_sleep_ms = 10;
 // Mutex for LVGL task state (to modify task_running state)
 static bool task_running = false;
 
+lv_disp_t* displayHandle = nullptr;
+
 static void lvgl_task(void* arg);
 
 static bool task_lock(TickType_t timeout) {
@@ -72,8 +74,6 @@ void lvgl_task_start() {
     assert(task_result == pdTRUE);
 }
 
-lv_disp_t* displayHandle = nullptr;
-
 static void lvgl_task(TT_UNUSED void* arg) {
     TT_LOG_I(TAG, "lvgl task started");
 

Boards/Simulator/Source/hal/SdlDisplay.h

@@ -4,9 +4,11 @@
 #include <Tactility/hal/Display.h>
 #include <memory>
 
+/** Hack: variable comes from LvglTask.cpp */
 extern lv_disp_t* displayHandle;
 
 class SdlDisplay final : public tt::hal::Display {
+
 public:
 
     std::string getName() const final { return "SDL Display"; }