feat(gridnav): add lv_gridnav (#2911)

* add first implememtation

* Update src/extra/others/gridnav/lv_gridnav.c

Co-authored-by: embeddedt <42941056+embeddedt@users.noreply.github.com>

* minor fix

* add example and minor fixes

* add more examples

* add more examples

* code formatting

* add LV_GRIDNAC_CTRL_SCROLL_FIRST

* code formatting

* add example for list

* add docs

* Misc:  improvements to gridnav docs (#2994)

Co-authored-by: embeddedt <42941056+embeddedt@users.noreply.github.com>
Co-authored-by: Ken Carpenter <62639971+FoundationKen@users.noreply.github.com>

examples/widgets/list/lv_example_list_1.c

@@ -10,6 +10,7 @@ static void event_handler(lv_event_t * e)
         LV_LOG_USER("Clicked: %s", lv_list_get_btn_text(list1, obj));
     }
 }
+
 void lv_example_list_1(void)
 {
     /*Create a list*/