fix a11y crash seen on close of tdf#92573

its not the reported crash, which has "gone away" which might
be a duplicate of tdf#90502

the switch only handled RES_TITLE_CHANGED and RES_DESCRIPTION_CHANGED so if its
anything else, e.g. OBJ_DYING, then don't attempt GetNoTextNode

Change-Id: I642beb66613481cbc7ee18647f0204a67d670a84

sw/source/core/access/accnotextframe.cxx

@@ -102,6 +102,9 @@ void SwAccessibleNoTextFrame::Modify( const SfxPoolItem* pOld, const SfxPoolItem
             return; // probably was deleted - avoid doing anything
     }
 
+    if (nWhich != RES_TITLE_CHANGED || nWhich != RES_DESCRIPTION_CHANGED)
+        return;
+
     const SwNoTextNode *pNd = GetNoTextNode();
     OSL_ENSURE( pNd == aDepend.GetRegisteredIn(), "invalid frame" );
     switch( nWhich )