[POWERPC] disable PReP and EFIKA during make oldconfig

New boards should not be enabled per default.
Disable EFIKA and PReP per default.
Anyone who really needes the new code can enable it during make oldconfig.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/Kconfig

@@ -436,7 +436,7 @@ config PPC_EFIKA
 	select RTAS_PROC
 	select PPC_MPC52xx
 	select PPC_NATIVE
-	default y
+	default n
 
 config PPC_LITE5200
 	bool "Freescale Lite5200 Eval Board"
@@ -471,7 +471,7 @@ config PPC_PREP
 	select PPC_INDIRECT_PCI
 	select PPC_UDBG_16550
 	select PPC_NATIVE
-	default y
+	default n
 
 config PPC_MAPLE
 	depends on PPC_MULTIPLATFORM && PPC64