ARM: initial DTS support for km_kirkwood

This is a first attempt to support the km_kirkwood reference design with
a device tree. This km_kirkwood design is present in many Keymile
products. It is based on the Marvell Bobcat SOC which integrates a
Kirkwood CPU next to a big L2 Ethernet Switch. The Kirkwood in the SOC
is very similar to the "normal" one, but there are a few differences.

This initial support is minimal: the kernel can boot with network
(ge0), serial port and NAND functional.

Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
Cc: Holger Brunck <holger.brunck@keymile.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/arch/arm/mach-kirkwood/Kconfig b/arch/arm/mach-kirkwood/Kconfig
index d033b7a..50bca50 100644
--- a/arch/arm/mach-kirkwood/Kconfig
+++ b/arch/arm/mach-kirkwood/Kconfig
@@ -123,6 +123,13 @@
 	  Say 'Y' here if you want your kernel to support the
 	  Iomega StorCenter ix2-200 (Flattened Device Tree).
 
+config MACH_KM_KIRKWOOD_DT
+	bool "Keymile Kirkwood Reference Design (Flattened Device Tree)"
+	select ARCH_KIRKWOOD_DT
+	help
+	  Say 'Y' here if you want your kernel to support the
+	  Keymile Kirkwood Reference Desgin, using Flattened Device Tree.
+
 config MACH_TS219
 	bool "QNAP TS-110, TS-119, TS-119P+, TS-210, TS-219, TS-219P and TS-219P+ Turbo NAS"
 	help