tools: bpftool: dual license all files

Currently bpftool contains a mix of GPL-only and GPL or BSD2
licensed files.  Make sure all files are dual licensed under
GPLv2 and BSD-2-Clause.

Signed-off-by: Jakub Kicinski <[email protected]>
Acked-by: Roman Gushchin <[email protected]>
Acked-by: YueHaibing <[email protected]>
Acked-by: Yonghong Song <[email protected]>
Acked-by: Stanislav Fomichev <[email protected]>
Acked-by: Sean Young <[email protected]>
Acked-by: Jiri Benc <[email protected]>
Acked-by: David Calavera <[email protected]>
Acked-by: Andrey Ignatov <[email protected]>
Acked-by: Joe Stringer <[email protected]>
Acked-by: David Ahern <[email protected]>
Acked-by: Alexei Starovoitov <[email protected]>
Acked-by: Petar Penkov <[email protected]>
Acked-by: Sandipan Das <[email protected]>
Acked-by: Prashant Bhole <[email protected]>
Acked-by: Stephen Hemminger <[email protected]>
Acked-by: John Fastabend <[email protected]>
Acked-by: Taeung Song <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
CC: [email protected]
Signed-off-by: Daniel Borkmann <[email protected]>

tools/bpf/bpftool/btf_dumper.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /* Copyright (c) 2018 Facebook */
 
 #include <ctype.h>

tools/bpf/bpftool/cgroup.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0+
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 // Copyright (C) 2017 Facebook
 // Author: Roman Gushchin <[email protected]>
 

tools/bpf/bpftool/jit_disasm.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /*
  * Based on:
  *

tools/bpf/bpftool/json_writer.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /*
  * Simple streaming JSON writer
  *

tools/bpf/bpftool/json_writer.h

@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
 /*
  * Simple streaming JSON writer
  *

tools/bpf/bpftool/map_perf_ring.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /* Copyright (C) 2018 Netronome Systems, Inc. */
 /* This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public

tools/bpf/bpftool/net.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0+
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 // Copyright (C) 2018 Facebook
 
 #define _GNU_SOURCE

tools/bpf/bpftool/netlink_dumper.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0+
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 // Copyright (C) 2018 Facebook
 
 #include <stdlib.h>

tools/bpf/bpftool/netlink_dumper.h

@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0+ */
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
 // Copyright (C) 2018 Facebook
 
 #ifndef _NETLINK_DUMPER_H_

tools/bpf/bpftool/perf.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0+
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 // Copyright (C) 2018 Facebook
 // Author: Yonghong Song <[email protected]>