[libxslt] xslt: Remove declaration for old libxml2

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 896f3ce7bf6b29b22991d3df3029329fe5e9963c
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Tue Sep 6 14:16:20 2022 +0200

    xslt: Remove declaration for old libxml2

 libxslt/xslt.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)
---
diff --git a/libxslt/xslt.c b/libxslt/xslt.c
index 69116f2b..468e97ec 100644
--- a/libxslt/xslt.c
+++ b/libxslt/xslt.c
@@ -91,13 +91,7 @@ const xmlChar *xsltXSLTAttrMarker = (const xmlChar *) "LRE XSLT Attr";
 #ifdef XSLT_LOCALE_WINAPI
 extern xmlRMutexPtr xsltLocaleMutex;
 #endif
-/*
- * Harmless but avoiding a problem when compiling against a
- * libxml <= 2.3.11 without LIBXML_DEBUG_ENABLED
- */
-#ifndef LIBXML_DEBUG_ENABLED
-double xmlXPathStringEvalNumber(const xmlChar *str);
-#endif
+
 /*
  * Useful macros
  */