Edje entry: Skip codes for updating cursor when cursor position is not changed

Edje entry: Skip codes for updating cursor when cursor position is not changed

Summary:
When ever a Edje's cursor function is called, "cursor,changed" signal is
emitted. Even if the position is not changed. And, in Elementary, the signal
will trigger evas_smart_objects_calculate() from elm_widget_show_region_set().
It causes bad performace.
@fix

Test Plan: N/A

Reviewers: tasn, herdsman, cedric, woohyun

Subscribers: jpeg, z-wony, Blackmole

Differential Revision: https://phab.enlightenment.org/D3902