Update licence text for iwlwifi firmware

Just an extension of the copyright dates.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

LICENCE.iwlwifi_firmware

-Copyright (c) 2006-2010, Intel Corporation.
+Copyright (c) 2006-2012, Intel Corporation.
 All rights reserved.
 
 Redistribution.  Redistribution and use in binary form, without