sched/numa: fix setting of cpupid on page migration twice

Commit 7851a45cd3 ("mm: numa: Copy cpupid on page migration") copiess
over the cpupid at page migration time.  It is unnecessary to set it
again in migrate_misplaced_transhuge_page().

Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/migrate.c

@@ -1753,8 +1753,6 @@ int migrate_misplaced_transhuge_page(struct mm_struct *mm,
 	if (!new_page)
 		goto out_fail;
 
-	page_cpupid_xchg_last(new_page, page_cpupid_last(page));
-
 	isolated = numamigrate_isolate_page(pgdat, page);
 	if (!isolated) {
 		put_page(new_page);