add LittlevGL demo

add LittlevGL demo on stm32f746 discovery board

components/gui/LittlevGL/3rdparty/lv_examples/lv_examples.h

@@ -0,0 +1,55 @@
+/**
+ * @file lv_examples.h
+ *
+ */
+
+#ifndef LV_EXAMPLES_H
+#define LV_EXAMPLES_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*********************
+ *      INCLUDES
+ *********************/
+#include "../lvgl/lvgl.h"
+
+/*********************
+ *      DEFINES
+ *********************/
+/*Test  lvgl version*/
+#define LV_EXAMPLES_LVGL_REQ_MAJOR  6
+#define LV_EXAMPLES_LVGL_REQ_MINOR  0
+#define LV_EXAMPLES_LVGL_REQ_PATCH  0
+
+#if LV_EXAMPLES_LVGL_REQ_MAJOR != LVGL_VERSION_MAJOR
+#error "lv_examples: Wrong lvgl major version"
+#endif
+
+#if LV_EXAMPLES_LVGL_REQ_MINOR > LVGL_VERSION_MINOR
+#error "lv_examples: Wrong lvgl minor version"
+#endif
+
+#if LV_EXAMPLES_LVGL_REQ_PATCH > LVGL_VERSION_PATCH
+#error "lv_examples: Wrong lvgl bug fix version"
+#endif
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ * GLOBAL PROTOTYPES
+ **********************/
+
+/**********************
+ *      MACROS
+ **********************/
+
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /*LV_EXAMPLES_H*/