efl_input_clickable: add longpress_abort

efl_input_clickable: add longpress_abort

Now, a specific class which uses efl_input_clickable_util is able
to cancel ongoing longpress event by calling longpress_abort.

This commit shows how efl_ui_text uses longpress_abort to satisfy
its own longpress use case

ref T7847

Reviewed-by: Marcel Hollerbach <mail@marcel-hollerbach.de>
Differential Revision: https://phab.enlightenment.org/D9455