This patch for dpt_i2o fixes TCQ stuff, but doesn't solve DMA mapping
issues (so it still doesn't work, but it's not because of TCQ).

Getting around to fixing DMA mapping API issues is much more work per
driver than the TCQ stuff, so I'm putting it off until later.

dpti.h:
  Update template
dpt_i2o.c:
  Update to new TCQ scheme