debian/copyright: Add GPL/X11 Dual License

Quite a few Device-Tree files are licensed under GPL/X11 Dual License,
which was not tracked in debian/copyright.

License wording may differ a bit, and there may comes new DTS on every
release, therefore it's almost impossible to make a accurate list.
Here I added the files list that I confirmed which is under GPL/X11
Dual License.

debian/copyright

@@ -21,6 +21,23 @@ Files: debian/rules.d/tools/hv/check-hyperv.c
 Copyright: 2011 Lennart Poettering
 License: LGPL-2.1
 
+Files:
+ arch/arm/boot/dts/armada-370-*.dts* (except arch/arm/boot/dts/armada-370-seagate-*)
+ arch/arm64/boot/dts/amlogic/*.dts*
+ arch/arm64/boot/dts/cavium/thunder-*.dts*
+ arch/arm64/boot/dts/freescale/fsl-*.dts*
+ arch/arm64/boot/dts/marvell/armada-*.dts*
+ arch/arm64/boot/dts/marvell/berlin4ct-*.dts*
+ arch/arm64/boot/dts/rockchip/rk33*.dts*
+ arch/arm64/boot/dts/socionext/uniphier-ld*.dts*
+ arch/arm64/boot/dts/zte/zx296718*.dts*
+ include/dt-bindings/clock/sun*.h
+ include/dt-bindings/dma/axi-dmac.h
+ include/dt-bindings/dma/sun4i-a10.h
+ include/dt-bindings/pinctrl/sun4i-a10.h
+ include/dt-bindings/reset/sun*.h
+License: GPL-3+ or X11 Dual License
+
 Files: drivers/crypto/vmx/*.pl
 Copyright: 2006,2014 Andy Polyakov <appro@openssl.org>
 License: CRYPTOGAMS
@@ -162,3 +179,42 @@ License: LGPL-2.1
  .
  On Debian systems, the complete text of the GNU Lesser General Public
  License version 2.1 can be found in `/usr/share/common-licenses/LGPL-2.1'.
+
+License: GPL-3+ or X11 Dual License
+ This file is dual-licensed: you can use it either under the terms
+ of the GPL or the X11 license, at your option. Note that this dual
+ licensing only applies to this file, and not this project as a
+ whole.
+ .
+  a) This file 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 file 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.
+ .
+ Or, alternatively,
+ .
+  b) Permission is hereby granted, free of charge, to any person
+     obtaining a copy of this software and associated documentation
+     files (the "Software"), to deal in the Software without
+     restriction, including without limitation the rights to use,
+     copy, modify, merge, publish, distribute, sublicense, and/or
+     sell copies of the Software, and to permit persons to whom the
+     Software is furnished to do so, subject to the following
+     conditions:
+ .
+     The above copyright notice and this permission notice shall be
+     included in all copies or substantial portions of the Software.
+ .
+     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+     OTHER DEALINGS IN THE SOFTWARE.