ARM: uniphier: merge ph1_ld4_defconfig and ph1_sld8_defconfig

These two are similar enough to be merged into a single
defconfig file.  Distinguish one from another by "DEVICE_TREE"
from the command line.  The how-to-build in doc/README.uniphier
should be also updated.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/doc/README.uniphier b/doc/README.uniphier
index 57b947b..68cc05d 100644
--- a/doc/README.uniphier
+++ b/doc/README.uniphier
@@ -32,18 +32,18 @@
     $ make ph1_sld3_defconfig
     $ make CROSS_COMPILE=arm-linux-gnueabi-
 
-PH1-LD4:
-    $ make ph1_ld4_defconfig
+PH1-LD4 reference board:
+    $ make uniphier_ld4_sld8_defconfig
     $ make CROSS_COMPILE=arm-linux-gnueabi-
 
+PH1-sLD8 reference board:
+    $ make uniphier_ld4_sld8_defconfig
+    $ make CROSS_COMPILE=arm-linux-gnueabi- DEVICE_TREE=uniphier-ph1-sld8-ref
+
 PH1-Pro4:
     $ make ph1_pro4_defconfig
     $ make CROSS_COMPILE=arm-linux-gnueabi-
 
-PH1-sLD8:
-    $ make ph1_sld8_defconfig
-    $ make CROSS_COMPILE=arm-linux-gnueabi-
-
 PH1-Pro5:
     $ make ph1_pro5_defconfig
     $ make CROSS_COMPILE=arm-linux-gnueabi-