Fix/Update copyright notices; Add SPDX annotation
Let's fix some erroneous/accidential references to wrong license,
update copyright information where applicable and introduce a
SPDX-License-Identifier to all files.
Change-Id: I39af26c6aaaf5c926966391f6565fc5936be21af
diff --git a/src/gsm/gsm0502.c b/src/gsm/gsm0502.c
index 6b69893..53259a4 100644
--- a/src/gsm/gsm0502.c
+++ b/src/gsm/gsm0502.c
@@ -4,6 +4,8 @@
* (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
* All Rights Reserved
*
+ * SPDX-License-Identifier: GPL-2.0+
+ *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or