ARM: uniphier: compile board data only for SPL

Now U-Boot proper need not get the uniphier_boards array.  Compile
it only for SPL.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/mach-uniphier/Makefile b/arch/arm/mach-uniphier/Makefile
index abfdccc..166b41f 100644
--- a/arch/arm/mach-uniphier/Makefile
+++ b/arch/arm/mach-uniphier/Makefile
@@ -4,6 +4,7 @@
 
 ifdef CONFIG_SPL_BUILD
 
+obj-y += boards.o
 obj-y += spl_board_init.o
 obj-y += memconf.o
 obj-y += bcu/
@@ -21,7 +22,6 @@
 
 endif
 
-obj-y += boards.o
 obj-y += soc-info.o
 obj-y += boot-mode/
 obj-y += clk/