ox-html: Remove extra HTML_HEAD, HTML_HEAD_EXTRA

* ox-html.el (html): Fix typo.

lisp/ox-html.el

@@ -114,8 +114,6 @@
     (:html-link-use-abs-url nil "html-link-use-abs-url" org-html-link-use-abs-url)
     (:html-link-home "HTML_LINK_HOME" nil org-html-link-home)
     (:html-link-up "HTML_LINK_UP" nil org-html-link-up)
-    (:html-head "HTML_HEAD" nil org-html-head newline)
-    (:html-head-extra "HTML_HEAD_EXTRA" nil org-html-head-extra newline)
     (:html-container "HTML_CONTAINER" nil org-html-container-element)
     (:html-mathjax "HTML_MATHJAX" nil "" space)
     (:html-html5-fancy nil "html5-fancy" org-html-html5-fancy)