ext4: fix setting of referenced bit in ext4_es_lookup_extent()

We were setting referenced bit on the extent structure we return from
ext4_es_lookup_extent() which is just a private structure on stack. Thus
setting had no effect. Set the bit in the structure in the status tree
instead.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

fs/ext4/extents_status.c

@@ -823,8 +823,8 @@ int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
 		es->es_lblk = es1->es_lblk;
 		es->es_len = es1->es_len;
 		es->es_pblk = es1->es_pblk;
-		if (!ext4_es_is_referenced(es))
-			ext4_es_set_referenced(es);
+		if (!ext4_es_is_referenced(es1))
+			ext4_es_set_referenced(es1);
 		stats->es_stats_cache_hits++;
 	} else {
 		stats->es_stats_cache_misses++;