[SCSI] zfcp: Dont block zfcp_wq with scan

When running the scsi_scan from the zfcp workqueue and the target
device does not respond, the zfcp workqueue can block until the
scsi_scan hits a timeout. Move the work to the scsi host workqueue,
since this one is also used for the scan from the SCSI midlayer.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index 616c60f..5a01ef9 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -97,9 +97,7 @@
 	ccw_device_set_online(adapter->ccw_device);
 
 	zfcp_erp_wait(adapter);
-	wait_event(adapter->erp_done_wqh,
-		   !(atomic_read(&unit->status) &
-				ZFCP_STATUS_UNIT_SCSI_WORK_PENDING));
+	flush_work(&unit->scsi_work);
 
 	down(&zfcp_data.config_sema);
 	zfcp_unit_put(unit);
@@ -279,6 +277,7 @@
 
 	atomic_set(&unit->refcount, 0);
 	init_waitqueue_head(&unit->remove_wq);
+	INIT_WORK(&unit->scsi_work, zfcp_scsi_scan);
 
 	unit->port = port;
 	unit->fcp_lun = fcp_lun;