mm,memory_hotplug: drop status_change_nid parameter from memory_notify

mm,memory_hotplug: drop status_change_nid parameter from memory_notify

There no users left of status_change_nid, so drop it from memory_notify
struct.

Link: https://lkml.kernel.org/r/20250616135158.450136-12-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Suggested-by: David Hildenbrand <david@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>