[POWERPC] Put mpc52xx support file in platforms/52xx

platforms/embedded6xx is probably going away, and 52xx boards need
some extra support the 52xx interrupt controller and DMA engine
anyway.  It makes sense to group all the 52xx bits into a single path.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 836caf1..a6bc221 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -410,6 +410,10 @@
 	select PPC_NATIVE
 	default y
 
+config PPC_MPC52xx
+	bool
+	default n
+
 config PPC_EFIKA
 	bool "bPlan Efika 5k2. MPC5200B based computer"
 	depends on PPC_MULTIPLATFORM && PPC32