powerpc: Move 32-bit probe() machine to later in the boot process

This converts all the 32-bit platforms to use the expanded device-tree
which is a pretty mechanical change. Unlike 64-bit, the 32-bit kernel
didn't rely on platform initializations to setup the MMU since it
sets it up entirely before probe_machine() so the move has comparatively
less consequences though it's a bigger patch.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/52xx/media5200.c

@@ -242,7 +242,7 @@ static const char * const board[] __initconst = {
  */
 static int __init media5200_probe(void)
 {
-	return of_flat_dt_match(of_get_flat_dt_root(), board);
+	return of_device_compatible_match(of_root, board);
 }
 
 define_machine(media5200_platform) {