Should return FALSE; not NULL

git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@3357 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/win/rfb_win32/ListViewControl.cxx b/win/rfb_win32/ListViewControl.cxx
index 12e0400..bd375e2 100644
--- a/win/rfb_win32/ListViewControl.cxx
+++ b/win/rfb_win32/ListViewControl.cxx
@@ -63,7 +63,7 @@
   lvI.pszText = texts[0]; 									  
   
   if(ListView_InsertItem(GetDlgItem(hDlg, idListView), &lvI) == -1)
-    return NULL;
+    return FALSE;
   
   for (i =1; i < columns; i++) {	
     SetLVItemText(