block: move PM request support to IDE

This removes the request types and hacks from the block code and into the
old IDE driver.  There is a small amunt of code duplication due to this,
but it's not too bad.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --cc block/blk-core.c
Simple merge

diff --cc block/blk-exec.c
Simple merge

diff --cc block/blk.h
Simple merge

diff --cc drivers/ide/ide-eh.c
Simple merge

diff --cc drivers/ide/ide-io.c
Simple merge

diff --cc drivers/ide/ide-pm.c
Simple merge

diff --cc drivers/ide/ide-taskfile.c
Simple merge

diff --cc include/linux/blkdev.h
Simple merge

diff --cc include/linux/ide.h
Simple merge