Fix playing same track after it has faded out

If a track was restarted after it faded out, then it wouldn't play. This
is because currentsong wasn't set to -1 after fading out, and that is
because the fade out calls pause() instead of haltdasmusik() when it
finishes.

Unlike f196fcd896, this fixes the time
trial music while keeping it to the same behavior as 2.2, and fixes
every single possible case that this music bug could have happened.

desktop_version/src/Music.cpp

@@ -330,7 +330,7 @@ void musicclass::processmusicfadeout(void)
 	{
 		musicVolume = 0;
 		m_doFadeOutVol = false;
-		pause();
+		haltdasmusik();
 	}
 }