Back up importing not working as intended

[tekktrik]

Fix inbound shortly, just a placeholder so I don't forget - but basically I think the import logic doesn't reflect the intent of allowing pwmio if audioio isn't available , since my QTPy-ESP32-S2 should be able to use this library with pwmio but the current import structure doesn't allow it. It seems like it should only tell the user to add adafruit_waveform if audioio is detected by adafruit_waveform is not based on the logic here:

Adafruit_CircuitPython_RTTTL/adafruit_rtttl.py

Lines 190 to 205 in 695e52c

	if AUDIOIO_AVAILABLE:
	wave, min_freq = _get_wave(tune, octave)
	try:
	# AudioOut interface changed in CP 3.x; a waveform if now pass
	# directly to .play(), generated for each note in _play_to_pin()
	if sys.implementation.version[0] >= 3:
	base_tone = audioio.AudioOut(pin)
	else:
	base_tone = audioio.AudioOut(pin, wave)
	except ValueError:
	# No DAC on the pin so use PWM.
	pass
	# Fall back to PWM
	if not base_tone:
	base_tone = pwmio.PWMOut(pin, duty_cycle=0, variable_frequency=True)