isci: make sgl explicit/aligned request object member

Towards unifying request objects we need all members to be defined in the
object and not carved out of anonymous buffer space.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 12f2df9..7d5f793 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -298,14 +298,10 @@
 		goto out;
 
 	/* let the core do it's construct. */
-	status = scic_task_request_construct(
-		&isci_host->sci,
-		sci_device,
-		SCI_CONTROLLER_INVALID_IO_TAG,
-		request,
-		request->sci_request_mem_ptr,
-		&request->sci_request_handle
-		);
+	status = scic_task_request_construct(&isci_host->sci, sci_device,
+					     SCI_CONTROLLER_INVALID_IO_TAG,
+					     request, &request->sci_req,
+					     &request->sci_request_handle);
 
 	if (status != SCI_SUCCESS) {
 		dev_warn(&isci_host->pdev->dev,