[libxml2] Add LIBXML_VALID_ENABLED to xmlreader

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 386fb27654b93d9fb2880e03fb508d618a2e66f1
Author: Łukasz Wojniłowicz <lukasz wojnilowicz gmail com>
Date:   Tue Apr 28 17:00:37 2020 +0200

    Add LIBXML_VALID_ENABLED to xmlreader
    
    There are already LIBXML_VALID_ENABLED in this file to guard against
    "--without-valid" at "./configure" step, but here they were missing.

 xmlreader.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/xmlreader.c b/xmlreader.c
index 687c8b3c..e39d0388 100644
--- a/xmlreader.c
+++ b/xmlreader.c
@@ -2260,6 +2260,7 @@ xmlFreeTextReader(xmlTextReaderPtr reader) {
     if (reader->ctxt != NULL) {
         if (reader->dict == reader->ctxt->dict)
            reader->dict = NULL;
+#ifdef LIBXML_VALID_ENABLED
        if ((reader->ctxt->vctxt.vstateTab != NULL) &&
            (reader->ctxt->vctxt.vstateMax > 0)){
             while (reader->ctxt->vctxt.vstateNr > 0)
@@ -2268,6 +2269,7 @@ xmlFreeTextReader(xmlTextReaderPtr reader) {
            reader->ctxt->vctxt.vstateTab = NULL;
            reader->ctxt->vctxt.vstateMax = 0;
        }
+#endif /* LIBXML_VALID_ENABLED */
        if (reader->ctxt->myDoc != NULL) {
            if (reader->preserve == 0)
                xmlTextReaderFreeDoc(reader, reader->ctxt->myDoc);