Socket.accept() always blocking

[bludin]

Socket.accept() is always blocking because

Adafruit_CircuitPython_Wiznet5k/adafruit_wiznet5k/adafruit_wiznet5k_socketpool.py

Lines 416 to 419 in 4502430

	if (
	self._timeout
	and 0 < self._timeout < ticks_diff(ticks_ms(), stamp) / 1000
	):

doesn't differentiate between self._timeout being None or zero