Update copyright dates to include 2012.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@12843 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/helgrind/hg_errors.c b/helgrind/hg_errors.c
index abe3a0d..1d7d50e 100644
--- a/helgrind/hg_errors.c
+++ b/helgrind/hg_errors.c
@@ -8,7 +8,7 @@
    This file is part of Helgrind, a Valgrind tool for detecting errors
    in threaded programs.
 
-   Copyright (C) 2007-2011 OpenWorks Ltd
+   Copyright (C) 2007-2012 OpenWorks Ltd
       info@open-works.co.uk
 
    This program is free software; you can redistribute it and/or