Correct scaling of max power for Super Speed
Correct scaling of max power for Super Speed

The 'MaxPower' field of the Configuration descriptor is in units of 2mA
for everything pre-dating Super Speed and in units of 8mA for Super
Speed. Also, it is actually a current (measured in Amps), not a power
(measured in Watts); so the previous docstring was wrong/misleading when
it talked about mW (milliwatts).

vpelletier/python-libusb1,vpelletier/python-libusb1