Add root LICENSE and LICENSES/ with full license texts

Consolidate the project licensing into a single root LICENSE that explains
the BSD-3-Clause core (Copyright (c) 2009 free60.org) and inventories every
bundled third-party component by license: BSD-3-Clause, MIT, the Broadcom
CFE/USB license, public domain, GPL-2.0, GPL-3.0, LGPL-2.1, and the
dual-licensed libfdt. Add a LICENSES/ directory containing the full
verbatim text of each license used in the repository.

Remove the now-redundant libxenon/LICENSE and devkitxenon/LICENSE; their
contents are superseded by the root LICENSE.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: Swizzy

LICENSE

@@ -0,0 +1,110 @@
+LibXenon — Licensing
+====================
+
+LibXenon is a bare-metal homebrew library for the Xbox 360.
+
+The library's own source code is licensed under the 3-clause BSD license
+(Copyright (c) 2009 free60.org). This is the license that applies to the
+project as a whole and to any file that does not state otherwise.
+
+This repository also bundles a number of third-party components. Each of
+those keeps the license declared in its own source files; the BSD license
+does not override them. The full text of every license used in this
+repository is provided in the LICENSES/ directory.
+
+If you redistribute LibXenon, in source or binary form, you must satisfy
+the conditions of every license that covers the parts you ship. Pay
+particular attention to the GPL- and LGPL-licensed components: linking
+them into your program can place copyleft obligations on the result.
+
+Where this file and a source-file header disagree, the header wins.
+
+
+Licenses used in this repository
+--------------------------------
+
+Each license below has its full text in LICENSES/.
+
+  SPDX identifier        Full text
+  ---------------------  -------------------------------------------
+  BSD-3-Clause           LICENSES/BSD-3-Clause.txt
+  MIT                    LICENSES/MIT.txt
+  GPL-2.0                LICENSES/GPL-2.0.txt
+  GPL-3.0                LICENSES/GPL-3.0.txt
+  LGPL-2.1               LICENSES/LGPL-2.1.txt
+  LicenseRef-Broadcom-CFE   LICENSES/LicenseRef-Broadcom-CFE.txt
+  LicenseRef-Public-Domain  LICENSES/LicenseRef-Public-Domain.txt
+
+
+Component breakdown
+-------------------
+
+3-clause BSD (BSD-3-Clause)
+  * All original LibXenon code that carries no other header.
+        Copyright (c) 2009 free60.org
+  * libxenon/drivers/console/console.c     — Copyright (c) 2009 Georg Lukas
+  * libxenon/drivers/crypt/hmac_sha1.{c,h} — Copyright (c) 1998,2000 Aaron D. Gifford
+  * libxenon/drivers/diskio/disc_io.h      — Copyright (c) 2006 Michael "Chishm" Chisholm
+  * libxenon/drivers/elf/elf_abi.h         — Copyright (c) 1995-2002 Erik Theisen
+  * libxenon/drivers/iso9660/*             — KallistiOS; Copyright (c) Dan Potter et al.
+  * libxenon/drivers/lwip/*                — lwIP; Copyright (c) Swedish Institute
+                                             of Computer Science and contributors
+  * libxenon/drivers/utils/gmon.{c,h}      — Copyright (c) 1983,1992,1993 The Regents
+                                             of the University of California
+  * devkitxenon/examples/*                 — LibXenon example code
+
+MIT
+  * libxenon/drivers/xenos/xenos_edid.{c,h} — Copyright (c) Luc Verhaegen,
+                                              Intel Corp., Dennis Munsie
+  * libxenon/ports/xenon/bin2s.c            — Copyright (c) 2003-2005 Damian Yerrick
+
+LicenseRef-Broadcom-CFE (permissive; from Broadcom's CFE / USB stack)
+  Redistribution in source and binary form is permitted; the copyright
+  notice and conditions must be retained, and the Broadcom name may not
+  be used for endorsement.
+  * libxenon/drivers/nocfe/*                — Copyright (c) 2000-2003 Broadcom Corp.
+  * libxenon/drivers/usb/*  (except tinyehci) — Copyright (c) 2000-2005 Broadcom Corp.,
+                                              with Xbox 360 controller additions by
+                                              Felix Domke and others
+
+LicenseRef-Public-Domain
+  * libxenon/drivers/crypt/sha1.c           — Steve Reid / Aaron D. Gifford
+  * toolchain/build-xenon-toolchain         — Uwe Hermann, Felix Domke
+
+GNU GPL, version 2 (GPL-2.0)
+  * libxenon/drivers/elf/elf.c              — Copyright (c) 2010-2011 Hector Martin
+                                              "marcan" (GPLv2 only)
+  * libxenon/drivers/usb/tinyehci/*         — based on the Linux ehci-hcd driver,
+                                              Copyright (c) 2001 David Brownell
+                                              (GPLv2 or, at your option, later)
+
+GNU GPL, version 3 or later (GPL-3.0)
+  * libxenon/drivers/diskio/ata.c           — from GRUB, Copyright (c) 2007
+                                              Free Software Foundation, Inc.
+
+GNU LGPL, version 2.1 (LGPL-2.1)
+  * libxenon/drivers/crypt/des.c            — Copyright (c) 2006-2007 Christophe Devine
+
+Dual-licensed — GPL-2.0 (or later) OR BSD-3-Clause, at your option
+  * libxenon/drivers/libfdt/*               — Copyright (c) 2006 David Gibson,
+                                              IBM Corporation
+
+
+Build toolchain and auxiliary libraries
+---------------------------------------
+
+  * The Makefile / build glue (devkitxenon/rules and related) derives from
+    devkitPRO and is GPL-licensed.
+  * The patches under toolchain/ (binutils, gcc, newlib) are modifications
+    to the corresponding GNU projects and are covered by those projects'
+    licenses (GPL).
+  * zlib, libpng, bzip2 and FreeType are downloaded and built by
+    toolchain/build-xenon-toolchain. They are NOT stored in this
+    repository and remain under their own upstream licenses (Zlib,
+    libpng, bzip2, and the FreeType License / GPL respectively).
+
+
+This summary is a guide to help you locate the governing terms. It does
+not modify any of the licenses it refers to. The authoritative source for
+any file is that file's own header together with the corresponding full
+license text in LICENSES/.

LICENSES/BSD-3-Clause.txt

@@ -0,0 +1,11 @@
+Copyright (c) <year> <owner>. 
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.