[libxml2] Add a couple of misisng check in xmlRelaxNGCleanupTree

[Daniel Veillard <veillard src gnome org>]

commit 54c4b1aa719beb83d6fa34181d33b5496e26f4da
Author: Gaurav Gupta <g gupta samsung com>
Date:   Mon Jul 14 16:14:44 2014 +0800

    Add a couple of misisng check in xmlRelaxNGCleanupTree
    
    For https://bugzilla.gnome.org/show_bug.cgi?id=733041
    
    check cur->parent before dereferencing the pointer even if
    a null parent there should not happen
    Also fix a typo

 relaxng.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)
---
diff --git a/relaxng.c b/relaxng.c
index 4273db3..57ae972 100644
--- a/relaxng.c
+++ b/relaxng.c
@@ -7343,13 +7343,13 @@ xmlRelaxNGCleanupTree(xmlRelaxNGParserCtxtPtr ctxt, xmlNodePtr root)
                     if (ns != NULL)
                         xmlFree(ns);
                    /*
-                    * Since we are about to delete cur, if it's nsDef is non-NULL we
+                    * Since we are about to delete cur, if its nsDef is non-NULL we
                     * need to preserve it (it contains the ns definitions for the
                     * children we just moved).  We'll just stick it on to the end
                     * of cur->parent's list, since it's never going to be re-serialized
                     * (bug 143738).
                     */
-                   if (cur->nsDef != NULL) {
+                   if ((cur->nsDef != NULL) && (cur->parent != NULL)) {
                        xmlNsPtr parDef = (xmlNsPtr)&cur->parent->nsDef;
                        while (parDef->next != NULL)
                            parDef = parDef->next;
@@ -7367,7 +7367,8 @@ xmlRelaxNGCleanupTree(xmlRelaxNGParserCtxtPtr ctxt, xmlNodePtr root)
         else if ((cur->type == XML_TEXT_NODE) ||
                  (cur->type == XML_CDATA_SECTION_NODE)) {
             if (IS_BLANK_NODE(cur)) {
-                if (cur->parent->type == XML_ELEMENT_NODE) {
+                if ((cur->parent != NULL) &&
+                   (cur->parent->type == XML_ELEMENT_NODE)) {
                     if ((!xmlStrEqual(cur->parent->name, BAD_CAST "value"))
                         &&
                         (!xmlStrEqual