ARM: cns3xxx: enable V6K instead of plain V6

The cns3xxx is an ARM11MPCore which has all the V6K extensions, so V6K
should be selected instead. Dropping the select will use the default for
ARCH_MULTI_V6 which is V6K.
Signed-off-by: NRob Herring <robh@kernel.org>
Cc: Anton Vorontsov <anton@enomsg.org>

arch/arm/mach-cns3xxx/Kconfig

@@ -3,7 +3,6 @@ config ARCH_CNS3XXX
 	select ARM_GIC
 	select MIGHT_HAVE_PCI
 	select PCI_DOMAINS if PCI
-	select CPU_V6
 	help
 	  Support for Cavium Networks CNS3XXX platform.