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/pseudotalloc/pseudotalloc.c b/src/pseudotalloc/pseudotalloc.c
index b77ffe9..2a99066 100644
--- a/src/pseudotalloc/pseudotalloc.c
+++ b/src/pseudotalloc/pseudotalloc.c
@@ -1,7 +1,26 @@
 /*! \file pseudotalloc.c
  * overly simplistic talloc replacement for deeply embedded
  * microcontrollers.  Obviously this has none of the properties of real
- * talloc, it is particualrly not hierarchical at all. */
+ * talloc, it is particualrly not hierarchical at all.
+ *
+ * (C) 2017 by Harald Welte <laforge@gnumonks.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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
 
 #include "talloc.h"
 #include <string.h>