1. To support instantaneous report for SCSI device existing by periodic
   polling
2. In arcmsr_iop_xfer(), inform AP of F/W's deadlock state to prevent
   endless waiting
3. To block the coming SCSI command while the driver is handling bus reset
4. To support HW reset in bus reset error handler
Signed-off-by: NNick Cheng <nick.cheng@areca.com.tw>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>