Wing Commander AGA. The A1200 port of the CD32 version places the afterburner on Fire 2. Weirdly, other buttons are not used even if you have a CD32 joypad or
something that's compatible.
*EDIT* Correction: It doesn't support a two-button joystick! It just supports my CD32 clone pad in a half-assed manner that I mentioned above :/ I just tried that pad with other 2-button games, and none of the buttons are recognized as Fire2.