* lisp/filecache.el: Fix cycling (bug#49761).

* lisp/filecache.el: Fix cycling (bug#49761).

(file-cache-cycle): Refactor from file-cache-minibuffer-complete.
(file-cache-minibuffer-complete): Use file-cache-cycle in 2 old places,
and in 1 following new place.  When last-command is equal to this-command,
use file-cache-cycle to continue cycling the previous completion
as long as the user continues typing C-TAB.
Also when displaying a list of completions, don't try to move point
to the common prefix.