wrong number of cpu's is reported on some specific platforms.

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first platform:
server with X4 Intel® Xeon® E5-4620 (8 physical, 16 logical), running 
a 64bit Windows Server 2012 R2 Standard.
results:
os.cpu_count() reports 64 units
psutil.cpu_count(logical=False) reports 32 units
psutil.cpu_count(logical=True) reports 64 units

multiprocessing using concurrent.futures able to fully utilize the server;

***

second platform:
server with X2 Intel® Xeon® Gold 6138 (20 physical, 40 logical), running a 64bit Windows Server 2016 Standard.
results:
os.cpu_count() reports 128 units
psutil.cpu_count(logical=False) reports 20 units
psutil.cpu_count(logical=True) reports 40 units

multiprocessing using concurrent.futures able to utilize only 1/4 of the server's power;