Use a non-recursive replace function when the parser supports it.

https://bugs.gnu.org/29782
https://bugzilla.samba.org/show_bug.cgi?id=9515
https://bugzilla.gnome.org/show_bug.cgi?id=736077 (for xsltproc)

Patch copied from Debian:
https://salsa.debian.org/debian/docbook-xsl/-/blob/master/debian/patches/765567_non-recursive_string_subst.patch

Description: use EXSLT "replace" function when available
 A recursive implementation  of string.subst is problematic,
 long strings with many matches will cause stack overflows.
Author: Peter De Wachter <pdewacht@gmail.com>
Bug-Debian: https://bugs.debian.org/750593

--- a/lib/lib.xsl
+++ b/lib/lib.xsl
@@ -6,7 +6,11 @@
 
      This module implements DTD-independent functions
 
-     ******************************************************************** --><xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
+     ******************************************************************** -->
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+                xmlns:str="http://exslt.org/strings"
+                exclude-result-prefixes="str"
+                version="1.0">
 
 <xsl:template name="dot.count">
   <!-- Returns the number of "." characters in a string -->
@@ -52,6 +56,9 @@
   <xsl:param name="replacement"/>
 
   <xsl:choose>
+    <xsl:when test="function-available('str:replace')">
+      <xsl:value-of select="str:replace($string, string($target), string($replacement))"/>
+    </xsl:when>
     <xsl:when test="contains($string, $target)">
       <xsl:variable name="rest">
         <xsl:call-template name="string.subst">
'>
<input type='hidden' name='id' value='5d08c05d22369ff405a47b0681b37c05a550a6c8'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=5d08c05d22369ff405a47b0681b37c05a550a6c8'>root</a>/<a href='/guix/log/gnu?id=5d08c05d22369ff405a47b0681b37c05a550a6c8'>gnu</a>/<a href='/guix/log/gnu/tests?id=5d08c05d22369ff405a47b0681b37c05a550a6c8'>tests</a>/<a href='/guix/log/gnu/tests/version-control.scm?id=5d08c05d22369ff405a47b0681b37c05a550a6c8'>version-control.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/tests/version-control.scm?id=5d08c05d22369ff405a47b0681b37c05a550a6c8&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-04-29 18:07:17 +0200'>2022-04-29</span></td><td><a href='/guix/commit/gnu/tests/version-control.scm?id=73eeeeafbb0765f76834b53c9fe6cf3c8f740840'>tests: Avoid starting services to check whether they're running.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-10-06 07:18:01 +0000'>2021-10-06</span></td><td><a href='/guix/commit/gnu/tests/version-control.scm?id=5ec0c48fd457c9f68f0cbaa3b7dec9dc780b17ae'>tests: gitile: Increase VM memory size.</a><span class='msg-avail'>...</span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2021-09-26 23:20:56 +0200'>2021-09-26</span></td><td><a href='/guix/commit/gnu/tests/version-control.scm?id=89b05442933d92f4b21c3294455a498e8333727d'>tests: Reduce boilerplate for users of 'system-test-runner'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-09-25 18:52:05 +0200'>2021-09-25</span></td><td><a href='/guix/commit/gnu/tests/version-control.scm?id=1fb75128a5202b406622da6272bc809c46d1f439'>tests: Adjust to SRFI-64 as found in Guile 3.0.7.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-09-02 22:56:55 +0200'>2021-09-02</span></td><td><a href='/guix/commit/gnu/tests/version-control.scm?id=c60daa8e9dfa5f641ecb5f4f3a9135e27b58d2d7'>gnu: version-control: Add gitile service.</a><span class='msg-avail'>...</span></td><td>Julien Lepiller</td></tr>