This is a followup to Doug's comments and older work.  It kills
sdev->tagged_queue which wasn't ever set in 2.5/2.6 except through
obscure and broken ioctls (!).  As a reason of that tagged queing
didn't work for a lot of drivers, so this does change behaviour.
Be careful..

James, can you review the code in 53c700.c?  Calling scsi_activate_tcq
in ->queuecommand rather than ->slave_configure looks rather strange to
me..