ARM: uniphier: move CONFIG_ARMV8_MULTIENTRY to Kconfig

I just did not notice this option had an entry in Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/mach-uniphier/Kconfig b/arch/arm/mach-uniphier/Kconfig
index 175c9f7..89be0b3 100644
--- a/arch/arm/mach-uniphier/Kconfig
+++ b/arch/arm/mach-uniphier/Kconfig
@@ -11,6 +11,7 @@
 	bool
 	select ARM64
 	select SPL_SEPARATE_BSS
+	select ARMV8_MULTIENTRY
 
 choice
         prompt "UniPhier SoC select"