[POWERPC] 4xx Kconfig cleanup

Remove some leftover cruft in the 40x Kconfig file.  Also make sure we
select WANT_DEVICE_TREE for 40x.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index e4b2aee..643bee2 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -40,6 +40,7 @@
 config 40x
 	bool "AMCC 40x"
 	select PPC_DCR_NATIVE
+	select WANT_DEVICE_TREE
 
 config 44x
 	bool "AMCC 44x"