scsi: qla2xxx: target: Improve checks in qlt_xmit_response() / qlt_rdy_to_xfer()

scsi: qla2xxx: target: Improve checks in qlt_xmit_response() / qlt_rdy_to_xfer()

Similar fixes to both functions:

qlt_xmit_response:

 - If the cmd cannot be processed, remember to call ->free_cmd() to
   prevent the target-mode midlevel from seeing a cmd lockup.

 - Do not try to send the response if the exchange has been terminated.

 - Check for chip reset once after lock instead of both before and after
   lock.

 - Give errors from qlt_pre_xmit_response() a lower priority to
   compensate for removing the first check for chip reset.

qlt_rdy_to_xfer:

 - Check for chip reset after lock instead of before lock to avoid
   races.

 - Do not try to receive data if the exchange has been terminated.

 - Give errors from qlt_pci_map_calc_cnt() a lower priority to
   compensate for moving the check for chip reset.

Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Link: https://patch.msgid.link/cd6ccd31-33fa-4454-be36-507bf578a546@cybernetics.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>