Multiple analogWrites reset the PWM period on each write

[earlephilhower]

The following test shows on a logic analyzer that the PWM period is reset from the beginning on a pin which is used with analogWrite().

const int pin = D3;
void setup() {
  pinMode(pin,OUTPUT);
  analogWriteFreq(1000);
  analogWriteRange(1000);
}
void loop() {
  analogWrite(pin, 1);
}

This results in an improper 1-PWM-cycle ratio, and if called in a loop as shown can give a significantly different PWM result that desired.