ARM: UniPhier: select CONFIG_SPL

Now UniPhier platform is only supported with SPL.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2b0d2c9..5eb1d03 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -800,6 +800,7 @@
 	bool "Panasonic UniPhier platform"
 	select CPU_V7
 	select SUPPORT_SPL
+	select SPL
 	select OF_CONTROL if !SPL_BUILD
 
 endchoice