ARM: uniphier: add ProXstream2 and PH1-LD6b support

The DDR SDRAM initialization code has not been mainlined yet, but
U-Boot proper should work.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/dts/uniphier-ph1-ld6b-ref.dts b/arch/arm/dts/uniphier-ph1-ld6b-ref.dts
index ca68930..bd86f093 100644
--- a/arch/arm/dts/uniphier-ph1-ld6b-ref.dts
+++ b/arch/arm/dts/uniphier-ph1-ld6b-ref.dts
@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
  *
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 /dts-v1/;