refs #780, avoid assert

In the past we used one situation list, now a map (per callsign).
The assert was checking if the callsign is really correct for that situation, now we can just set the callsign.

src/blackmisc/interpolator.cpp

@@ -33,8 +33,7 @@ namespace BlackMisc
         Q_ASSERT_X(!callsign.isEmpty(), Q_FUNC_INFO, "empty callsign");
 
         auto currentSituation = this->getInterpolatedSituation(this->remoteAircraftSituations(callsign), currentTimeSinceEpoc, isVtolAircraft, status);
-
-        Q_ASSERT_X(currentSituation.getCallsign() == callsign, Q_FUNC_INFO, "mismatching callsigns");
+        currentSituation.setCallsign(callsign); // make sure callsign is correct
         return currentSituation;
     }