dired-x largely cosmetic changes.

dired-x largely cosmetic changes.

* lisp/dired-x.el (dired-clean-up-after-deletion, dired-do-relsymlink)
(dired-do-relsymlink-regexp, dired-find-buffer-nocreate): Use #'.
(dired-hack-local-variables): Use inhibit-read-only.
(dired-guess-default): Simplify.
(dired-make-relative-symlink): Use dotimes.
(dired-simultaneous-find-file): Use dolist.
(dired-mark-sexp): Remove unneeded `if'.  Use line-end-position.
(dired-x-hands-off-my-keys): Doc fix.
(dired-x-bind-find-file): Doc fix.  Use remapping.
(after-init-hook): No need to add dired-x-bind-find-file.
(dired-x-find-file, dired-x-find-file-other-window): Doc fixes.
No need to call expand-file-name.
(dired-filename-at-point): Remove unused locals `end', `filename'.