I'll take a guess (not having seen the icon in person) that it has something to do with distance to destination - or how long your next putt will be! Doesn't the owner's manual mention it?
That icon is showing you that you have selected the Trip A trip meter (see attached, top right column). You have the choice of selecting either Trip A, Trip B or Total.
You can switch between either trip meters or total in the Stats when you go to clear them when gassing up. When you're in one of the tabs (Trip A or B or Total) you punch the joystick up and that makes that meter show up in the main screen. The flag icon seems to indicate a trip number. Can't wait to see what else is new.