objects: Rename 'fields' import to 'obj_fields'
objects: Rename 'fields' import to 'obj_fields'

Otherwise we overload the import with the 'fields' variable defined on
the class.

Change-Id: Ife4646eb8da78cc25baddddfd3eb8c7d360352b3
Signed-off-by: Stephen Finucane <492121341a95b3c3aab646bed44634f739dd019b@redhat.com>

rahulunair/nova,rahulunair/nova,mahak/nova,rahulunair/nova,klmitch/nova,klmitch/nova,mahak/nova,openstack/nova,openstack/nova,klmitch/nova,klmitch/nova,mahak/nova,openstack/nova