Don't reset timetrialparlost every frame during countdown

Otherwise, if the timer ticked up past the par (via using the unfocus
pause or pause menu), it would result in the sad squeak being played
every frame because the game would constantly be setting
timetrialparlost, then moving to the code block below, assuming that
since timetrialparlost that we haven't lost the par already, and playing
the squeak.

timetrialparlost gets reset in hardreset() and startgamemode() anyways,
so there's no need to be constantly resetting this variable.

Fixes #699.

desktop_version/src/Logic.cpp

@@ -731,7 +731,6 @@ void gamelogic(void)
 
             if (game.timetrialcountdown > 0)
             {
-                game.timetrialparlost = false;
                 game.hascontrol = true;
                 game.timetrialcountdown--;
                 if (game.timetrialcountdown > 30)