Corrects 2nd argument type for logging
Corrects 2nd argument type for logging

Fixes a regression introduced in commit
c73afa9fd1df14bff9186c1e73ac8f3593ef81db.

This completely breaks Horizon in last
DevStack version.

Change-Id: Ib754c6ea325534399a34ff76a290475ac652fea9
Fixes: bug #1122958

CCI-MOC/python-novaclient,ntt-sic/python-novaclient,akash1808/python-novaclient,Shihta/python-novaclient,citrix-openstack-build/python-novaclient,metacloud/python-novaclient,guptaankita/python-novaclient,ntt-sic/python-novaclient,Shihta/python-novaclient,JioCloud/python-novaclient,guptaankita/python-novaclient,JioCloud/python-novaclient,metacloud/python-novaclient,citrix-openstack-build/python-novaclient,mat128/python-novaclient,akash1808/python-novaclient,takeshineshiro/python-novaclient,CCI-MOC/python-novaclient,mat128/python-novaclient,takeshineshiro/python-novaclient