flash_image: use Override_Active_Slot instead of bootctrl

Change-Id: I985d644ccb1e3bc8f9f9da77798d7bbcb7b84419
diff --git a/gui/action.cpp b/gui/action.cpp
index 819e4ad..d5b8c8f 100755
--- a/gui/action.cpp
+++ b/gui/action.cpp
@@ -1801,9 +1801,9 @@
 		string current_slot = PartitionManager.Get_Active_Slot_Display();
 		bool pre_op_status = PartitionManager.Flash_Image(path, filename);
 
-		PartitionManager.Set_Active_Slot(current_slot == "A" ? "B" : "A");
+		PartitionManager.Override_Active_Slot(current_slot == "A" ? "B" : "A");
 		op_status = (int) !(pre_op_status && PartitionManager.Flash_Image(path, filename));
-		PartitionManager.Set_Active_Slot(current_slot);
+		PartitionManager.Override_Active_Slot(current_slot);
 
 		DataManager::SetValue("tw_flash_both_slots", 0);
 		flag = false;
@@ -2360,4 +2360,4 @@
 	}
 	operation_end(op_status);
 	return 0;
-}
\ No newline at end of file
+}