Update content to docbook-4.x since we do not have 3.x available in MacPorts
--- doc/fontconfig-devel.sgml.orig	2012-07-23 21:01:32.000000000 -0500
+++ doc/fontconfig-devel.sgml	2012-11-28 21:42:04.000000000 -0600
@@ -1,4 +1,4 @@
-<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
+<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V4.2//EN" [
 <!ENTITY fcatomic SYSTEM "fcatomic.sgml">
 <!ENTITY fcblanks SYSTEM "fcblanks.sgml">
 <!ENTITY fccache SYSTEM "fccache.sgml">
--- doc/fontconfig-user.sgml.orig	2025-07-02 00:46:34
+++ doc/fontconfig-user.sgml	2026-04-02 14:00:10
@@ -1,4 +1,4 @@
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V3.1//EN" [
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.2//EN" [
 <!ENTITY cacheversion SYSTEM "cache-version.sgml">
 <!ENTITY version SYSTEM "version.sgml">
 <!ENTITY confdir SYSTEM "confdir.sgml">