Btrfs: fix page cache memory leak

Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
index 2f95fc6..2881341 100644
--- a/fs/btrfs/print-tree.c
+++ b/fs/btrfs/print-tree.c
@@ -1,6 +1,7 @@
 #include <linux/module.h>
 #include "ctree.h"
 #include "disk-io.h"
+#include "print-tree.h"
 
 void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l)
 {