bug#52263: Stale comment in xsd-regexp.el about Emacs not supporting Unicode

[Stefan Kangas]

Severity: minor

I believe this comment in lisp/nxml/xsd-regexp.el can be removed as
Emacs supports Unicode now:

    ;; The semantics of XSD regexps are defined in terms of Unicode.
    ;; Non-Unicode characters are not allowed in regular expressions and
    ;; will not match against the generated regular expressions.  A
    ;; Unicode character means a character in one of the Mule charsets
    ;; ascii, latin-iso8859-1, mule-unicode-0100-24ff,
    ;; mule-unicode-2500-33ff, mule-unicode-e000-ffff, eight-bit-control
    ;; or a character translatable to such a character (i.e a character
    ;; for which `encode-char' will return non-nil).
    ;;
    ;; 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
    ;; until the fabled Unicode version of Emacs makes an appearance.

Is that correct?