dont delete a side from carryover if it came back to life

the previous behaviour was inconsitent, since [team]lost= wasn't read when loading a savegame. So this doesn't break previous behaviour.

This especialy fixes the scenario "Stolen Gold" from "Northern Rebirth" (http://gna.org/bugs/?22601)

src/play_controller.cpp

@@ -1424,9 +1424,13 @@ void play_controller::check_victory()
 
 			if (remove_from_carryover_on_defeat_) 
 			{
-				tm.set_lost();
+				tm.set_lost(true);
 			}
 		}
+		else if(remove_from_carryover_on_defeat_)
+		{
+			tm.set_lost(false);
+		}
 
 		if (tm.is_human()) {
 			there_is_a_local_human = true;