of a data transfer operation immediately after the data transfer
was finished, instead of waiting for the chip to interrupt us and
tell us that it was finished and had the result for us. This worked
okay for read and write since the operation would be finished very
shortly after the data transfer completed. However, with formatting,
the chip still had most of the rest of the track to do, so we ended
up timing out before the operation was finished. This fix is from
sparc64/dev/fdc.c and was tested on sparc by tnn@.