添加按键高阻态、使飞控进入BOOT、擦除flash

app/drivers/sertrf/key.h

@@ -47,5 +47,15 @@ typedef struct {
 
 extern bool key_single_click,key_press_down,key_press_up;
 void _work_button(void *arg);
+/**
+ * @brief 初始化按键
+ */
 void button_work_init();
-void boot_set(uint8_t value);
+/**
+ * @brief 设置boot按键输出
+ */
+void boot_set(uint8_t value);
+/**
+ * @brief 设置boot按键为高阻态
+ */
+void boot_set_high_z(void);