IB/srp: Increase supported CDB size

Set the Scsi_Host's max_cmd_len from 12 (default) to 16 for
SRP. Otherwise scsi_dispatch_cmd() won't pass down certain commands
such as READ CAPACITY 16, required for supporting disks > 2TB.
Signed-off-by: Arne Redlich <arne.redlich@xiranet.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/ulp/srp/ib_srp.c

@@ -1716,7 +1716,8 @@ static ssize_t srp_create_target(struct class_device *class_dev,
 	if (!target_host)
 		return -ENOMEM;
 
-	target_host->max_lun = SRP_MAX_LUN;
+	target_host->max_lun     = SRP_MAX_LUN;
+	target_host->max_cmd_len = sizeof ((struct srp_cmd *) (void *) 0L)->cdb;
 
 	target = host_to_target(target_host);