ARM: highbank: enable big-endian

Apart from a xgmac driver issue, the highbank seems to work correctly in
big-endian mode. Allow the selection of big-endian in the system.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Rob Herring <rob.herring@calxeda.com>

arch/arm/mach-highbank/Kconfig

@@ -4,6 +4,7 @@ config ARCH_HIGHBANK
 	select ARCH_HAS_CPUFREQ
 	select ARCH_HAS_HOLES_MEMORYMODEL
 	select ARCH_HAS_OPP
+	select ARCH_SUPPORTS_BIG_ENDIAN
 	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select ARM_AMBA
 	select ARM_ERRATA_764369