add:fix编译lvgl demo报错

components/lvgl/lv_demos/lv_examples.h

@@ -14,6 +14,7 @@ extern "C" {
 /*********************
  *      INCLUDES
  *********************/
+#define LV_LVGL_H_INCLUDE_SIMPLE 1
 #if defined(LV_LVGL_H_INCLUDE_SIMPLE)
 #include "lvgl.h"
 #else