net_connections() raises TypeError on BSD platforms

[giampaolo]

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ERROR: test_connections.TestUnconnectedSockets.test_unix_tcp
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Traceback (most recent call last):
  File "/home/vagrant/psutil/psutil/tests/test_connections.py", line 180, in test_unix_tcp
    conn = self.check_socket(sock)
  File "/home/vagrant/psutil/psutil/tests/test_connections.py", line 116, in check_socket
    self.compare_procsys_connections(os.getpid(), cons)
  File "/home/vagrant/psutil/psutil/tests/test_connections.py", line 125, in compare_procsys_connections
    sys_cons = psutil.net_connections(kind=kind)
  File "/home/vagrant/psutil/psutil/__init__.py", line 2181, in net_connections
    return _psplatform.net_connections(kind)
  File "/home/vagrant/psutil/psutil/_psbsd.py", line 399, in net_connections
    raddr = _common.addr(*raddr)
TypeError: __new__() takes exactly 3 arguments (1 given)