qla2xxx: Honor FCP_RSP retry delay timer field.

Parse the retry delay timer field from the FCP response data and if:

- It is not zero
- The SCSI status is busy or queue full

return SCSI_MLQUEUE_TARGET_BUSY for the number of milliseconds specified
in the retry delay timer field.

Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/drivers/scsi/qla2xxx/qla_fw.h b/drivers/scsi/qla2xxx/qla_fw.h
index 7f2e1c7..42bb357 100644
--- a/drivers/scsi/qla2xxx/qla_fw.h
+++ b/drivers/scsi/qla2xxx/qla_fw.h
@@ -567,7 +567,7 @@
 #define SF_TRANSFERRED_DATA	BIT_11
 #define SF_FCP_RSP_DMA		BIT_0
 
-	uint16_t reserved_2;
+	uint16_t retry_delay;
 	uint16_t scsi_status;		/* SCSI status. */
 #define SS_CONFIRMATION_REQ		BIT_12