rename symbol: CONFIG_KIRKWOOD -> CONFIG_ARCH_KIRKWOOD

Have this symbol follow the pattern of all other such symbols.
This patch also removes a TODO from the code.

Reviewed-by: Chris Packham <judge.packham@gmail.com>
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 4d6716f..f7855c9 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -309,7 +309,7 @@
 
 config MVGBE
 	bool "Marvell Orion5x/Kirkwood network interface support"
-	depends on KIRKWOOD || ARCH_ORION5X
+	depends on ARCH_KIRKWOOD || ARCH_ORION5X
 	select PHYLIB if DM_ETH
 	help
 	  This driver supports the network interface units in the
diff --git a/drivers/net/mvgbe.c b/drivers/net/mvgbe.c
index b0b8d34..6d56360 100644
--- a/drivers/net/mvgbe.c
+++ b/drivers/net/mvgbe.c
@@ -24,7 +24,7 @@
 #include <asm/byteorder.h>
 #include <asm/arch/cpu.h>
 
-#if defined(CONFIG_KIRKWOOD)
+#if defined(CONFIG_ARCH_KIRKWOOD)
 #include <asm/arch/soc.h>
 #elif defined(CONFIG_ARCH_ORION5X)
 #include <asm/arch/orion5x.h>