misc elevator code cleanups

[Christoph Hellwig <hch@xxxxxx>]

Hi Jens,

this series has a bunch of random elevator cleanups.

Diffstat:
 blk-mq-sched.c |    7 --
 blk-mq.c       |    2 
 blk.h          |    1 
 elevator.c     |  175 +++++++++++++++++++++++----------------------------------
 4 files changed, 73 insertions(+), 112 deletions(-)