Revert common logging use in rootwrap

Revert recent plug of common logging into rootwrap, as it breaks
rootwrap logging. Rootwrap does not make use of oslo logging and oslo
config in order to reduce the surface of code run as root.

See https://review.openstack.org/#/c/26468/ for discussion.

Change-Id: I276ade164a902d091f9aafab79bbd4cc189588eb
Merge "Revert common logging use in rootwrap"