remove bdev->bd_super

Hi all,

this series is against the vfs.super branch in the VFS tree and removes the
bd_super field in struct block_device.

Diffstat:
 fs/buffer.c               |   11 +++--------
 fs/ext4/ext4_jbd2.c       |    3 +--
 fs/ext4/super.c           |    1 -
 fs/ocfs2/journal.c        |    6 +++---
 fs/romfs/super.c          |    1 -
 fs/super.c                |    3 ---
 include/linux/blk_types.h |    1 -
 7 files changed, 7 insertions(+), 19 deletions(-)