Fix regression caused by fix for CVE-2016-0718 when building with -DXML_UNICODE.

Discussion:

https://sourceforge.net/p/expat/bugs/539/

Patch copied from upstream source repository:

https://sourceforge.net/p/expat/code_git/ci/af507cef2c93cb8d40062a0abe43a4f4e9158fb2/

From af507cef2c93cb8d40062a0abe43a4f4e9158fb2 Mon Sep 17 00:00:00 2001
From: Sebastian Pipping <sebastian@pipping.org>
Date: Sun, 17 Jul 2016 20:22:29 +0200
Subject: [PATCH 1/2] Fix regression bug #539 (needs -DXML_UNICODE)

Thanks to Andy Wang and Karl Waclawek!
---
 expat/lib/xmlparse.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c
index b308e67..0d5dd7b 100644
--- a/lib/xmlparse.c
+++ b/lib/xmlparse.c
@@ -2468,7 +2468,7 @@ doContent(XML_Parser parser,
                        &fromPtr, rawNameEnd,
                        (ICHAR **)&toPtr, (ICHAR *)tag->bufEnd - 1);
             convLen = (int)(toPtr - (XML_Char *)tag->buf);
-            if ((convert_res == XML_CONVERT_COMPLETED) || (convert_res == XML_CONVERT_INPUT_INCOMPLETE)) {
+            if ((fromPtr >= rawNameEnd) || (convert_res == XML_CONVERT_INPUT_INCOMPLETE)) {
               tag->name.strLen = convLen;
               break;
             }
-- 
2.10.0
2641103880ce87b631e00e6212787747f694aa'>tree</a><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=572641103880ce87b631e00e6212787747f694aa'>commit</a><a href='/guix/diff/po/doc/guix-cookbook.fa.po?id=572641103880ce87b631e00e6212787747f694aa'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/po/doc/guix-cookbook.fa.po'>
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<div class='path'>path: <a href='/guix/log/?id=572641103880ce87b631e00e6212787747f694aa'>root</a>/<a href='/guix/log/po?id=572641103880ce87b631e00e6212787747f694aa'>po</a>/<a href='/guix/log/po/doc?id=572641103880ce87b631e00e6212787747f694aa'>doc</a>/<a href='/guix/log/po/doc/guix-cookbook.fa.po?id=572641103880ce87b631e00e6212787747f694aa'>guix-cookbook.fa.po</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/po/doc/guix-cookbook.fa.po?id=572641103880ce87b631e00e6212787747f694aa&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-10-17 22:10:25 +0200'>2021-10-17</span></td><td><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=15c91189cb61c579f4289047c79530cefe75215f'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-09-02 04:06:52 +0200'>2021-09-02</span></td><td><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=1ff2092a39dc5c7c7cd9b4a0ba4b59f92e738efc'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/it.po: New file.
* po/packages/LINGUAS: Add `it'.
* po/*/*.po: Update translations.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-08-04 14:49:53 +0200'>2021-08-04</span></td><td><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=6c10c96fedf707d7be059aeb79bd5c8e2d2fa210'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.ru.po: New file.
* po/doc/guix-cookbook.sk.po: New file.
* po/*/*.po: Update translations.
* doc/local.mk (COOKBOOK_LANGUAGES): Add ru and sk.
(info_TEXINFOS): Add Russian and Slovak cookbooks.
* po/doc/local.mk (DOC_COOKBOOK_PO_FILES): Add Russian and Slovak po
files.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-05-10 22:34:43 -0400'>2021-05-10</span></td><td><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=21fcced608c93e1ac836cdd9ab8c5d200c667e75'>nls: Update translations.</a></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-04-18 13:18:17 +0200'>2021-04-18</span></td><td><a href='/guix/commit/po/doc/guix-cookbook.fa.po?id=43fb84da6749a78d12ac0f13db4cecb435de7903'>nls: Add Persian translation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fa.po: New file.
* po/packages/LINGUAS: Add 'fa'.
* po/doc/guix-cookbook.fa.po: New file.
* po/doc/guix-manual.fa.po: New file.
* po/doc/local.mk (DOC_PO_FILES, DOC_COOKBOOK_PO_FILES): Add them.
* doc/local.mk (info_TEXINFOS): Add them.
</span></span></td><td>Julien Lepiller</td></tr>