memcg: rename mem_cgroup_zone_nr_pages() to mem_cgroup_zone_nr_lru_pages()

The caller of the function has been renamed to zone_nr_lru_pages(), and
this is just fixing up in the memcg code.  The current name is easily to
be mis-read as zone's total number of pages.

Signed-off-by: Ying Han <yinghan@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 2e8fbac..faa0a08 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -173,7 +173,7 @@
 				struct scan_control *sc, enum lru_list lru)
 {
 	if (!scanning_global_lru(sc))
-		return mem_cgroup_zone_nr_pages(sc->mem_cgroup, zone, lru);
+		return mem_cgroup_zone_nr_lru_pages(sc->mem_cgroup, zone, lru);
 
 	return zone_page_state(zone, NR_LRU_BASE + lru);
 }