[PATCH] remove blkdev_scsi_issue_flush_fn again

This function was removed a while ago, but crept in again via a recent
scsi merge.

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