spdx: initial adoption of licensing ID tags.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

Initially, only tag files that use BSD 4-Clause "Original" license.

RelNotes:	yes
Differential Revision:	https://reviews.freebsd.org/D13133

8 files changed, 18 insertions, 2 deletions

diff --git a/release/picobsd/tinyware/login/pathnames.h b/release/picobsd/tinyware/login/pathnames.h
index 333c2ca280fa..1984631aa944 100644
--- a/release/picobsd/tinyware/login/pathnames.h
+++ b/release/picobsd/tinyware/login/pathnames.h
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1989, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/login/pico-login.c b/release/picobsd/tinyware/login/pico-login.c
index e540ca861a51..080954c8bfcd 100644
--- a/release/picobsd/tinyware/login/pico-login.c
+++ b/release/picobsd/tinyware/login/pico-login.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1980, 1987, 1988, 1991, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/extern.h b/release/picobsd/tinyware/passwd/extern.h
index eae768c6e82a..0c6c9f505ec6 100644
--- a/release/picobsd/tinyware/passwd/extern.h
+++ b/release/picobsd/tinyware/passwd/extern.h
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/local_passwd.c b/release/picobsd/tinyware/passwd/local_passwd.c
index 33af88ac38c7..41b6fe998443 100644
--- a/release/picobsd/tinyware/passwd/local_passwd.c
+++ b/release/picobsd/tinyware/passwd/local_passwd.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1990, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/passwd.c b/release/picobsd/tinyware/passwd/passwd.c
index 42ebd8c1fd48..419396390afe 100644
--- a/release/picobsd/tinyware/passwd/passwd.c
+++ b/release/picobsd/tinyware/passwd/passwd.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1988, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/pw_copy.c b/release/picobsd/tinyware/passwd/pw_copy.c
index 753e1a67ff81..7586980e4a55 100644
--- a/release/picobsd/tinyware/passwd/pw_copy.c
+++ b/release/picobsd/tinyware/passwd/pw_copy.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1990, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/pw_util.c b/release/picobsd/tinyware/passwd/pw_util.c
index 1c163d2d57ed..cfab6e115269 100644
--- a/release/picobsd/tinyware/passwd/pw_util.c
+++ b/release/picobsd/tinyware/passwd/pw_util.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1990, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  *
diff --git a/release/picobsd/tinyware/passwd/pw_util.h b/release/picobsd/tinyware/passwd/pw_util.h
index 1000a9abdc7f..d441b1907966 100644
--- a/release/picobsd/tinyware/passwd/pw_util.h
+++ b/release/picobsd/tinyware/passwd/pw_util.h
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-4-Clause
+ *
  * Copyright (c) 1994
  *	The Regents of the University of California.  All rights reserved.
  *