image-dired-show-all-from-dir: Reuse dired's default-directory

image-dired-show-all-from-dir: Reuse dired's default-directory

* lisp/image/image-dired.el (image-dired-show-all-from-dir): Delegate
figuring out default-directory to dired.  This handles the case where
image-dired is called with a cons cell that has a directory in the car
and a list of files in the cdr, which dired can handle, and therefore
allows image-dired-show-all-from-dir to show an arbitrary list of
images.  It also means that image-dired-show-all-from-dir can handle
wildcards.
Ref: https://lists.gnu.org/r/emacs-devel/2025-01/msg00048.html

(cherry picked from commit d4503ccc2769035184e474542fc6c1df7e908ae0)