ARM: sunxi: Fix GPLv2 wording

During the GPL to GPL/X11 licensing migration, the GPL notice introduced
mentionned the device trees as a library, which is not really accurate. It
began to spread by copy and paste. Fix all these library mentions to reflect
the file that it's actually just a file.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/boot/dts/sun8i-a23.dtsi b/arch/arm/boot/dts/sun8i-a23.dtsi
index 6146ef1..6086adb 100644
--- a/arch/arm/boot/dts/sun8i-a23.dtsi
+++ b/arch/arm/boot/dts/sun8i-a23.dtsi
@@ -8,18 +8,18 @@
  * licensing only applies to this file, and not this project as a
  * whole.
  *
- *  a) This library is free software; you can redistribute it and/or
+ *  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 library is distributed in the hope that it will be useful,
+ *     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.
  *
  *     You should have received a copy of the GNU General Public
- *     License along with this library; if not, write to the Free
+ *     License along with this file; if not, write to the Free
  *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  *     MA 02110-1301 USA
  *