lv_arc_set_reverse: remove prototype with no implementation (#1741)

Required for Micropython

src/lv_widgets/lv_arc.h

@@ -159,14 +159,6 @@ void lv_arc_set_value(lv_obj_t * arc, int16_t value);
  */
 void lv_arc_set_range(lv_obj_t * arc, int16_t min, int16_t max);
 
-/**
- * Reverse arc behavior. The indicator will grow from arc end instead of arc start.
- * position.
- * @param arc pointer to a arc object
- * @param reverse true: enable disable reverse behavior; false: disable
- */
-void lv_arc_set_reverse(lv_obj_t * arc, bool reverse);
-
 /**
  * Set the threshold of arc knob increments
  * position.