view list: free style in base destructor.

typecast const char * to void * and pass ptr to free() since it doesn't modify the value pointed to,
either conceptually or in practice, it merely looks up the memory block using the pointer and deallocates it.

@fix

legacy/elementary/src/lib/elm_view_list.c

@@ -375,6 +375,7 @@ _elm_view_list_eo_base_destructor(Eo *obj, Elm_View_List_Data *priv)
          eo_event_callback_array_del(model_callbacks(), priv->rootdata));
 
    eo_do(priv->genlist, elm_obj_genlist_clear());
+   free((void *)priv->itc->item_style);
    elm_genlist_item_class_free(priv->itc);
 
    eina_hash_free(priv->prop_con);