elm_gengrid: remove all_items_deselect call in _gengrid_element_focused

focus_changed doesn't mean select_changed. selection is handled the code below.
Differential Revision: https://phab.enlightenment.org/D7268

src/lib/elementary/elm_gengrid.c

@@ -4285,7 +4285,6 @@ _gengrid_element_focused(void *data, const Efl_Event *ev)
         pd->last_focused_item = item;
      }
 
-   _all_items_deselect(pd);
    if (!_elm_config->item_select_on_focus_disable)
      {
         elm_gengrid_item_selected_set(item, EINA_TRUE);