reset GameTime properly if needed

dxx-changelog.txt

@@ -5,6 +5,7 @@ D1X-Rebirth Changelog
 arch/sdl/key.c: Added ENTER as Game key
 texmap/scanline.c: removed unreliable gr_fade_table check in c_tmap_scanline_per()
 arch/ogl/ogl.c, main/radar.c: don't show Radar box-fading in SDL; fixed OGL gr_ucircle()
+main/game.c: reset GameTime properly if needed
 
 20070219
 --------

main/game.c

@@ -3303,6 +3303,9 @@ void GameLoop(int RenderFlag, int ReadControlsFlag )
 		else
 			memset(&Controls, 0, sizeof(Controls));
 
+		if (GameTime < 0)
+			GameTime = 0;
+		
 		GameTime += FrameTime;
 
 		digi_sync_sounds();