* gnus-agent.el (gnus-agent-read-agentview, gnus-agent-save-alist)

* gnus-agent.el (gnus-agent-read-agentview, gnus-agent-save-alist)
(gnus-agent-expire-unagentized-dirs): Replace mapcar called for effect with
 while loop.

* gnus-art.el: Use mapc instead of mapcar to make gnus-article-* functions from
 article-* functions.
(gnus-multi-decode-header): Replace mapcar called for effect with dolist.

* gnus-bookmark.el (gnus-bookmark-bmenu-list)
(gnus-bookmark-show-details): Replace mapcar called for effect with while loop.

* gnus-diary.el (gnus-diary-update-group-parameters): Replace mapcar called for
 effect with while loop.

* gnus-group.el (gnus-group-suspend): Replace mapcar called for effect with
 dolist.

* gnus-registry.el (gnus-registry-split-fancy-with-parent): Replace mapcar
 called for effect with dolist.

* gnus-spec.el (gnus-correct-length): Make it simple and fast.

* gnus-sum.el (gnus-multi-decode-encoded-word-string)
(gnus-build-sparse-threads, gnus-summary-limit-include-expunged): Replace
 mapcar called for effect with dolist.
(gnus-simplify-buffer-fuzzy): Replace mapcar called for effect with mapc.

* gnus-topic.el (gnus-topic-find-groups, gnus-topic-move-group): Replace mapcar
 called for effect with dolist.
(gnus-topic-list): Replace mapcar called for effect with mapc.

* gnus.el: Use mapc instead of mapcar to add autoloads.