flag to clear, even when the COMMAND COMPLETE interrupt already did happen,
otherwise we get ATTENTION ERROR for next command if it happens soon
enough; this fixes the reliability problems introduced by previous change
some other cleanup & simlify of edc_cmd_wait()/edc_run_cmd(), the 'secs'
is just a hint used in !poll case only
add some comments
move status_block[] back to edc_mca_softc, to save stack memory
make #ifdef DEBUG #ifdef EDC_DEBUG and g/c some obsolete debug stuff
make some EAGAINs EIOs
edc_intr(): wakeup the waiter for any command, not just READ/WRITE DATA