efs: move headers out of include/linux/

Merge include/linux/efs_fs{_i,_dir}.h into fs/efs/efs.h.  efs_vh.h remains
there because this is the IRIX volume header and shouldn't really be
handled by efs but by the partitioning code.  efs_sb.h remains there for
now because it's exported to userspace.  Of course this wrong and aboot
should have a copy of it's own, but I'll leave that to a separate patch to
avoid any contention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>