isci: unify isci_host data structures

Make it explicit that isci_host and scic_sds_controller are one in the same
object.

Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>
[removed ->ihost back pointer]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index 36adc15..0521c04 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -201,7 +201,7 @@
 	 * we will let the core allocate the IO tag.
 	 */
 	status = scic_io_request_construct(
-		isci_host->core_controller,
+		&isci_host->sci,
 		sci_device,
 		SCI_CONTROLLER_INVALID_IO_TAG,
 		request,
@@ -394,7 +394,7 @@
 
 		/* send the request, let the core assign the IO TAG.	*/
 		status = scic_controller_start_io(
-			isci_host->core_controller,
+			&isci_host->sci,
 			sci_device,
 			request->sci_request_handle,
 			SCI_CONTROLLER_INVALID_IO_TAG
@@ -1186,7 +1186,7 @@
 						  );
 
 	/* complete the io request to the core. */
-	scic_controller_complete_io(isci_host->core_controller,
+	scic_controller_complete_io(&isci_host->sci,
 				    &isci_device->sci,
 				    request->sci_request_handle);
 	/* NULL the request handle so it cannot be completed or