[SCSI] qla2xxx: Generalize srb structure usage.

Lay groundwork for adding alternative asynchronous operations by
generalize and extending the SRB structure.  This allows for
follow-on patches to add support for:

- Asynchronous logins.
- ELS/CT passthru requests.
- Loopback requests.
- Non-blocking mailbox commands (ABTS, Task Management, etc).

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 68ab28c..9eb7be6 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -189,6 +189,7 @@
  */
 typedef struct srb {
 	struct fc_port *fcport;
+	uint32_t handle;
 
 	struct scsi_cmnd *cmd;		/* Linux SCSI command pkt */
 
@@ -196,6 +197,8 @@
 
 	uint32_t request_sense_length;
 	uint8_t *request_sense_ptr;
+
+	void *ctx;
 } srb_t;
 
 /*