mm/migration: remove unneeded local variable page_lru

We can use page_is_file_lru() directly to help account the isolated pages
to simplify the code a bit.

Link: https://lkml.kernel.org/r/20220318111709.60311-4-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/migrate.c

@@ -2013,7 +2013,6 @@ static struct page *alloc_misplaced_dst_page(struct page *page,
 
 static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 {
-	int page_lru;
 	int nr_pages = thp_nr_pages(page);
 	int order = compound_order(page);
 
@@ -2040,8 +2039,7 @@ static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page)
 	if (isolate_lru_page(page))
 		return 0;
 
-	page_lru = page_is_file_lru(page);
-	mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_lru,
+	mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_lru(page),
 			    nr_pages);
 
 	/*