ARM: 5995/1: ARM: Add L2x0 outer_sync() support (3/4)

The L2x0 cache controllers need to explicitly drain their write buffer
even for Normal Noncacheable memory accesses.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 88a24de..55a2a00 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -763,6 +763,7 @@
 		   REALVIEW_EB_A9MP || ARCH_MX35 || ARCH_MX31 || MACH_REALVIEW_PBX || ARCH_NOMADIK || ARCH_OMAP4
 	default y
 	select OUTER_CACHE
+	select OUTER_CACHE_SYNC
 	help
 	  This option enables the L2x0 PrimeCell.