various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

8 files changed, 24 insertions, 8 deletions

diff --git a/sbin/pfctl/parse.y b/sbin/pfctl/parse.y
index db09a44ad6b4..c976358325e7 100644
--- a/sbin/pfctl/parse.y
+++ b/sbin/pfctl/parse.y
@@ -1,6 +1,8 @@
 /*	$OpenBSD: parse.y,v 1.554 2008/10/17 12:59:53 henning Exp $	*/
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  * Copyright (c) 2001 Daniel Hartmeier.  All rights reserved.
  * Copyright (c) 2001 Theo de Raadt.  All rights reserved.
diff --git a/sbin/pfctl/pf_print_state.c b/sbin/pfctl/pf_print_state.c
index 346e6236f320..810c773f1019 100644
--- a/sbin/pfctl/pf_print_state.c
+++ b/sbin/pfctl/pf_print_state.c
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pf_print_state.c,v 1.52 2008/08/12 16:40:18 david Exp $	*/
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Daniel Hartmeier
  * All rights reserved.
  *
diff --git a/sbin/pfctl/pfctl.c b/sbin/pfctl/pfctl.c
index c00f4c3b8045..9586e1929991 100644
--- a/sbin/pfctl/pfctl.c
+++ b/sbin/pfctl/pfctl.c
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl.c,v 1.278 2008/08/31 20:18:17 jmc Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Daniel Hartmeier
  * Copyright (c) 2002,2003 Henning Brauer
  * All rights reserved.
diff --git a/sbin/pfctl/pfctl.h b/sbin/pfctl/pfctl.h
index 2c69bc2068b0..a432f109726a 100644
--- a/sbin/pfctl/pfctl.h
+++ b/sbin/pfctl/pfctl.h
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl.h,v 1.42 2007/12/05 12:01:47 chl Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Daniel Hartmeier
  * All rights reserved.
  *
diff --git a/sbin/pfctl/pfctl_parser.c b/sbin/pfctl/pfctl_parser.c
index a47dfd04103c..7786061839c9 100644
--- a/sbin/pfctl/pfctl_parser.c
+++ b/sbin/pfctl/pfctl_parser.c
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl_parser.c,v 1.240 2008/06/10 20:55:02 mcbride Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Daniel Hartmeier
  * Copyright (c) 2002,2003 Henning Brauer
  * All rights reserved.
diff --git a/sbin/pfctl/pfctl_parser.h b/sbin/pfctl/pfctl_parser.h
index 2b7fea7bf7a0..e652c97cf203 100644
--- a/sbin/pfctl/pfctl_parser.h
+++ b/sbin/pfctl/pfctl_parser.h
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl_parser.h,v 1.86 2006/10/31 23:46:25 mcbride Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2001 Daniel Hartmeier
  * All rights reserved.
  *
diff --git a/sbin/pfctl/pfctl_radix.c b/sbin/pfctl/pfctl_radix.c
index 5038e0b39ba2..6b303c6211f5 100644
--- a/sbin/pfctl/pfctl_radix.c
+++ b/sbin/pfctl/pfctl_radix.c
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl_radix.c,v 1.27 2005/05/21 21:03:58 henning Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2002 Cedric Berger
  * All rights reserved.
  *
diff --git a/sbin/pfctl/pfctl_table.c b/sbin/pfctl/pfctl_table.c
index f3a1efdd06ba..db338fbe0876 100644
--- a/sbin/pfctl/pfctl_table.c
+++ b/sbin/pfctl/pfctl_table.c
@@ -1,6 +1,8 @@
 /*	$OpenBSD: pfctl_table.c,v 1.67 2008/06/10 20:55:02 mcbride Exp $ */
 
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
  * Copyright (c) 2002 Cedric Berger
  * All rights reserved.
  *