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://anonscm.debian.org/cgit/collab-maint/docbook-xsl.git/tree/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
@@ -10,7 +10,10 @@
      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 -->
@@ -56,6 +59,9 @@
   <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">
 class='right' method='get' action='/guix/log/gnu/packages/accessibility.scm'>
<input type='hidden' name='id' value='e5e7a1676d23dc2f94f3a7a67e8463d24d966a74'/><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=e5e7a1676d23dc2f94f3a7a67e8463d24d966a74'>root</a>/<a href='/guix/log/gnu?id=e5e7a1676d23dc2f94f3a7a67e8463d24d966a74'>gnu</a>/<a href='/guix/log/gnu/packages?id=e5e7a1676d23dc2f94f3a7a67e8463d24d966a74'>packages</a>/<a href='/guix/log/gnu/packages/accessibility.scm?id=e5e7a1676d23dc2f94f3a7a67e8463d24d966a74'>accessibility.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/packages/accessibility.scm?id=e5e7a1676d23dc2f94f3a7a67e8463d24d966a74&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-03-18 15:05:08 +0100'>2019-03-18</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=47956fa0c24efcdcba3493f0231c30e9a39ec7df'>Correct name and email address for ng0.</a><span class='msg-avail'>...</span></td><td>ng0</td></tr>
<tr><td><span title='2019-02-08 23:50:53 +0100'>2019-02-08</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=1f6a970592d03b3600b483ad48e34568ae1f4e9a'>gnu: florence: Don't use NAME in source URI.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2019-02-05 10:07:52 +0100'>2019-02-05</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=16bb27f281298afcf7f7c2fb9200adf5d79c9e6c'>gnu: Add xmagnify.</a><span class='msg-avail'>...</span></td><td>Andrew Miloradovsky</td></tr>
<tr><td><span title='2018-05-25 14:01:40 +0200'>2018-05-25</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=e7ca985973e63543ff209e333c8b062ed5fdb9e5'>gnu: footswitch: Update to ca43d53f.</a><span class='msg-avail'>...</span></td><td>Jelle Licht</td></tr>
<tr><td><span title='2018-03-20 17:17:58 +0100'>2018-03-20</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=4a78fd4617908546be15d2c101f5cab512c71f8e'>Correct name and Email for ng0.</a><span class='msg-avail'>...</span></td><td>ng0</td></tr>
<tr><td><span title='2018-03-04 18:03:45 +0100'>2018-03-04</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=ed36949a9d0e5fd5582cc85e533c1ef8a8b2543e'>gnu: footswitch: Update to 0.1-2.deedd87.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-03-04 18:03:45 +0100'>2018-03-04</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=bd128d5e880ba73ce217e864f1cce6fe1b655ff1'>gnu: footswitch: Remove redundant MKDIR-P.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2017-11-19 12:13:43 +0200'>2017-11-19</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=c146314566b969d65d52621dec32bde0824f1207'>Update email address for ng0.</a></td><td>ng0</td></tr>
<tr><td><span title='2017-09-28 20:24:17 +0200'>2017-09-28</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=18a26f1c1300773ec01bc0afb86ca863b22fa285'>gnu: Add footswitch.</a><span class='msg-avail'>...</span></td><td>Stefan Reichör</td></tr>
<tr><td><span title='2017-05-27 13:35:02 -0400'>2017-05-27</span></td><td><a href='/guix/commit/gnu/packages/accessibility.scm?id=574e4e16d82bdc76b7c2ba726518047cdf1edf0b'>gnu: Add florence.</a><span class='msg-avail'>...</span></td><td>ng0</td></tr>