D5803: revert: added prompt before undeleting a file in -i(issue6008)

[Yuya Nishihara]

> +        if interactive:
> +            choice = repo.ui.promptchoice(
> +                _("Undelete file %s (Yn)?$$ &Yes $$ &No") % f)

Nit: "undelete" (no capital letter) per Mercurial's convention.

And I don't think "undelete" is good for user-facing messages. Perhaps, it
can be phrased as "add back removed file %s (Yn)?".