Updated openstack/openstack
Project: openstack/keystone  90e7a3854de9a9285a7af3d76dcd71d90a392b6e

remove default=None for config options

In the cfg module default=None is set as the default value.
It's not necessary to set default=None when defining new
parameters.

Closes-Bug: #1323975
Change-Id: Ibd52063cf30ca7b5565b09ed4602c15d5def3645