nilfs2: move inode count and block count into root object

This moves sbi->s_inodes_count and sbi->s_blocks_count into nilfs_root
object.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 2a6b74e..b75306d 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -856,9 +856,9 @@
 	raw_cp->cp_snapshot_list.ssl_next = 0;
 	raw_cp->cp_snapshot_list.ssl_prev = 0;
 	raw_cp->cp_inodes_count =
-		cpu_to_le64(atomic_read(&sbi->s_inodes_count));
+		cpu_to_le64(atomic_read(&sci->sc_root->inodes_count));
 	raw_cp->cp_blocks_count =
-		cpu_to_le64(atomic_read(&sbi->s_blocks_count));
+		cpu_to_le64(atomic_read(&sci->sc_root->blocks_count));
 	raw_cp->cp_nblk_inc =
 		cpu_to_le64(sci->sc_nblk_inc + sci->sc_nblk_this_inc);
 	raw_cp->cp_create = cpu_to_le64(sci->sc_seg_ctime);