Add SPDX annotation

Related: OS#3515
Change-Id: I3719bd8dc015569ecd81928fc079e27593cdca09
diff --git a/CommonLibs/Logger.cpp b/CommonLibs/Logger.cpp
index f68fab5..5db7f87 100644
--- a/CommonLibs/Logger.cpp
+++ b/CommonLibs/Logger.cpp
@@ -1,6 +1,7 @@
 /*
 * Copyright (C) 2018 sysmocom - s.f.m.c. GmbH
 *
+* SPDX-License-Identifier: AGPL-3.0+
 *
 * This software is distributed under the terms of the GNU Affero Public License.
 * See the COPYING file in the main directory for details.