[SCSI] dpt_i2o: return SCSI_MLQUEUE_HOST_BUSY when in reset

When the HBA is in reset we should be returning 'busy' and not
rely on the obscure 'last_reset' feature.

[jejb: checkpatch fixes]
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>