topology: mark a function as __init to save some memory

'topology_sysfs_init()' is only called via 'device_initcall'.
It can be marked as __init to save a few bytes of memory.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20200621081106.881915-1-christophe.jaillet@wanadoo.frSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/topology.c

@@ -133,7 +133,7 @@ static int topology_remove_dev(unsigned int cpu)
 	return 0;
 }
 
-static int topology_sysfs_init(void)
+static int __init topology_sysfs_init(void)
 {
 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
 				 "base/topology:prepare", topology_add_dev,