Providing API for the user to lock/unlock access to LVGL.

Author: aentinger

src/Braccio++.h

@@ -96,6 +96,9 @@ class BraccioClass
   inline bool isJoystickPressed_DOWN()   { return (digitalRead(BTN_DOWN) == LOW); }
   inline bool isButtonPressed_ENTER()    { return (digitalRead(BTN_ENTER) == LOW); }
 
+  inline void lvgl_lock  () { _display_mtx.lock(); }
+  inline void lvgl_unlock() { _display_mtx.unlock(); }
+
   static BraccioClass& get_default_instance() {
     static BraccioClass dev;
     return dev;