[POWERPC] Copy over headers from arch/ppc to arch/powerpc that we need

To build arch/powerpc without including asm-ppc/ we need these files
in asm-powerpc/

Moved some headers under arch/powerpc/platforms if they were only used by
platform or driver files and fixed up the source file includes to match
the new locations

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

arch/powerpc/platforms/embedded6xx/linkstation.c

@@ -18,9 +18,10 @@
 #include <asm/time.h>
 #include <asm/prom.h>
 #include <asm/mpic.h>
-#include <asm/mpc10x.h>
 #include <asm/pci-bridge.h>
 
+#include "mpc10x.h"
+
 static struct mtd_partition linkstation_physmap_partitions[] = {
 	{
 		.name   = "mtd_firmimg",