[POWERPC] Change topology_init() to a subsys_initcall

Change the powerpc version of topology_init() from an __initcall to
a subsys_initcall to match all other architectures.

Signed-off-by: Kevin Corry <kevcorry@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c
index 933e214..cae39d9 100644
--- a/arch/powerpc/kernel/sysfs.c
+++ b/arch/powerpc/kernel/sysfs.c
@@ -499,4 +499,4 @@
 
 	return 0;
 }
-__initcall(topology_init);
+subsys_initcall(topology_init);