Remove two functions obsolete since Emacs 23

* lisp/international/mule-cmds.el (unify-8859-on-encoding-mode)
(unify-8859-on-decoding-mode): Remove functions obsolete since
Emacs 23.
* lisp/nxml/xsd-regexp.el: Doc fix.

etc/NEWS

@@ -767,6 +767,9 @@ Use 'exif-parse-file' and 'exif-field' instead.
 ** 'insert-directory' alternatives should not change the free disk space line.
 This change is now applied in 'dired-insert-directory'.
 
+** Some functions obsolete since Emacs 23 have been removed:
+'unify-8859-on-encoding-mode', 'unify-8859-on-decoding-mode'.
+
 
 * Lisp Changes in Emacs 29.1
 

lisp/international/mule-cmds.el

@@ -3077,22 +3077,6 @@ on encoding."
                 0))
 	(substring enc2 i0 i2)))))
 
-;; Backwards compatibility.  These might be better with :init-value t,
-;; but that breaks loadup.
-(define-minor-mode unify-8859-on-encoding-mode
-  "Exists only for backwards compatibility."
-  :group 'mule
-  :global t)
-;; Doc said "obsolete" in 23.1, this statement only added in 24.1.
-(make-obsolete 'unify-8859-on-encoding-mode "don't use it." "23.1")
-
-(define-minor-mode unify-8859-on-decoding-mode
-  "Exists only for backwards compatibility."
-  :group 'mule
-  :global t)
-;; Doc said "obsolete" in 23.1, this statement only added in 24.1.
-(make-obsolete 'unify-8859-on-decoding-mode "don't use it." "23.1")
-
 (defvar ucs-names nil
   "Hash table of cached CHAR-NAME keys to CHAR-CODE values.")
 

lisp/nxml/xsd-regexp.el

@@ -52,9 +52,6 @@
 ;; or a character translatable to such a character (i.e a character
 ;; for which `encode-char' will return non-nil).
 ;;
-;; Using unify-8859-on-decoding-mode is probably a good idea here
-;; (and generally with XML and other Unicode-oriented formats).
-;;
 ;; Unfortunately, this means that this package is currently useless
 ;; for CJK characters, since there's no mule-unicode charset for the
 ;; CJK ranges of Unicode.  We should devise a workaround for this