Would this work instead? Although a simple if test would work with just two servos, the switch might be better if there's a chance of adding more servos later on. Also, why is the function type specifier int? Nothing is returned from the function call.
int servocontrol(int x)
{
 while (servoSwitchState == 0){
  potVal = digitalRead(potPin);
  angle = map(potVal, 0, 1023, 0, 179);
  switch (x) {
   case 1:
     myServo1.write(angle);
     break;
   case 2:
     myServo2.write(angle);
     break;
   default:
     // should never be here...
     break;
  }
Â
  if (digitalRead(4) == HIGH) {
   if (servoSwitchState == 0) {
    servoSwitchState = 1;
   } else {
    servoSwitchState = 0;
   }
  }
 }
}