docbook-xsl: restore nixos-specific patch

This reverts commit 3e7649f01b.

turns out that home-manager depends on it, and restoring this patch for
now seems preferrable to breaking home-manager until they move away from
docbook for their manpage generation.

pkgs/data/sgml+xml/stylesheets/xslt/docbook-xsl/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, substituteAll, fetchurl, fetchpatch, findXMLCatalogs, writeScriptBin, ruby, bash }:
+{ lib, stdenv, substituteAll, fetchurl, fetchpatch, findXMLCatalogs, writeScriptBin, ruby, bash, withManOptDedupPatch ? false }:
 
 let
 
@@ -36,6 +36,10 @@ let
           src = ./catalog-legacy-uris.patch;
           inherit legacySuffix suffix version;
         })
+      ] ++ lib.optionals withManOptDedupPatch [
+        # Fixes https://github.com/NixOS/nixpkgs/issues/166304
+        # https://github.com/docbook/xslt10-stylesheets/pull/241
+        ./fix-man-options-duplication.patch
       ];
 
       propagatedBuildInputs = [ findXMLCatalogs ];

pkgs/data/sgml+xml/stylesheets/xslt/docbook-xsl/fix-man-options-duplication.patch

@@ -0,0 +1,11 @@
+--- a/manpages/lists.xsl
++++ b/manpages/lists.xsl
+@@ -110,7 +110,7 @@
+   <xsl:text>.RE&#10;</xsl:text>
+ </xsl:template>
+ 
+-<xsl:template match="d:varlistentry/d:term"/>
++<xsl:template match="d:varlistentry/d:term" priority="1"/>
+ <xsl:template match="d:glossentry/d:glossterm"/>
+ 
+ <xsl:template match="d:variablelist[ancestor::d:listitem or ancestor::d:step or ancestor::d:glossdef]|