#define servoTarget1  50  // Minimum position of servo
#define servoTarget2  99  // Maximum position of servo
...
    int servoTarget = -1;  // Start out with servo in an unknown state.
...
    if (joy1Btn(3))   // Toggle the position of the servo...
    {
        if (servoTarget == servoTarget1)
            servoTarget = servoTarget2;
        else
            servoTarget = servoTarget1;

        servo[servo1] = servoTarget;
    }
...
}

Code:
#define servoTarget1  50  // Minimum position of servo
#define servoTarget2  99  // Maximum position of servo
...
    int servoTarget = -1;  // Start out with servo in an unknown state.

    bool b3Pressed = false; // This is the new piece -- This is a holder to let us know the state of the last press of the button
...
 /* Section within bluetooth scan loop */

    if (joy1Btn(3))   // Toggle the position of the servo...
    {
        if ( ! b3Pressed) // only deal with this if the previous scan was off!
        {         
            if (servoTarget == servoTarget1)
                servoTarget = servoTarget2;
            else
                servoTarget = servoTarget1;

            servo[servo1] = servoTarget;
       }
       b3Pressed = true;    // indicate that we're already pressed for the next scan through
    } else
      b3Pressed = false; // clear the "history" so we can tell that we've got a new button press
...
}

        buttonsPrev = 0;
        while (true)
        {
             getjoysticksettings(joystick);

             if (joystick.joy1_Buttons != buttonsPrev)
             {
                  buttonsPrev = joystick.joy1_Buttons;
                  if (joy1Btn(3))
                  {
                     // Do work
                  }

                  if (joy1Btn(2))
                  ....
             }
         }