SCI32: Add a game option to double the videos in KQ7 by default

Scaling works correctly with the Windows variant, which uses AVI files,
but the DOS variant uses Robot videos, and the way scaling is done
there is different, and is not working yet with KQ7 DOS. Nonetheless,
both versions are included in the game, so it's not a major issue.

common/gui_options.cpp

@@ -85,6 +85,9 @@ const struct GameOpt {
 	{ GUIO_GAMEOPTIONS10, "gameOptionA" },
 	{ GUIO_GAMEOPTIONS11, "gameOptionB" },
 	{ GUIO_GAMEOPTIONS12, "gameOptionC" },
+	{ GUIO_GAMEOPTIONS13, "gameOptionD" },
+	{ GUIO_GAMEOPTIONS14, "gameOptionE" },
+	{ GUIO_GAMEOPTIONS15, "gameOptionF" },
 
 	{ GUIO_NONE, nullptr }
 };