mm/hugetlb: a page from buddy is not on any list

The page allocated from buddy is not on any list, so just use list_add()
is enough.
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: https://lkml.kernel.org/r/20200831022351.20916-6-richard.weiyang@linux.alibaba.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/hugetlb.c

@@ -2416,7 +2416,7 @@ struct page *alloc_huge_page(struct vm_area_struct *vma,
 			h->resv_huge_pages--;
 		}
 		spin_lock(&hugetlb_lock);
-		list_move(&page->lru, &h->hugepage_activelist);
+		list_add(&page->lru, &h->hugepage_activelist);
 		/* Fall through */
 	}
 	hugetlb_cgroup_commit_charge(idx, pages_per_huge_page(h), h_cg, page);