arm64: dts: realtek: Change dual-license from MIT to BSD

Move the SPDX-License-Identifier to the top line and update to SPDX 2.0.
While at it, switch from GPLv2+/MIT to GPLv2+/BSD2c before adding more.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>

arch/arm64/boot/dts/realtek/rtd1295-zidoo-x9s.dts

+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * Copyright (c) 2016-2017 Andreas Färber
- *
- * SPDX-License-Identifier: (GPL-2.0+ OR MIT)
  */
 
 /dts-v1/;

arch/arm64/boot/dts/realtek/rtd1295.dtsi

+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * Realtek RTD1295 SoC
  *
  * Copyright (c) 2016-2017 Andreas Färber
- *
- * SPDX-License-Identifier: (GPL-2.0+ OR MIT)
  */
 
 #include "rtd129x.dtsi"

arch/arm64/boot/dts/realtek/rtd129x.dtsi

+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
 /*
  * Realtek RTD1293/RTD1295/RTD1296 SoC
  *
  * Copyright (c) 2016-2017 Andreas Färber
- *
- * SPDX-License-Identifier: (GPL-2.0+ OR MIT)
  */
 
 /memreserve/	0x0000000000000000 0x0000000000030000;