hugetlb, rmap: use hugepage_add_new_anon_rmap() in hugetlb_cow()

Obviously, setting anon_vma for COWed hugepage should be done
by hugepage_add_new_anon_rmap() to scan vmas faster.
This patch fixes it.

Signed-off-by: Naoya Horiguchi <[e-mail]>
Acked-by: Andrea Arcangeli <[e-mail]>
Reviewed-by: Rik van Riel <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

mm/hugetlb.c

···
 		set_huge_pte_at(mm, address, ptep,
 				make_huge_pte(vma, new_page, 1));
 		page_remove_rmap(old_page);
-		hugepage_add_anon_rmap(new_page, vma, address);
+		hugepage_add_new_anon_rmap(new_page, vma, address);
 		/* Make the old page be freed below */
 		new_page = old_page;
 		mmu_notifier_invalidate_range_end(mm,