[system-tests] Offloading and jumbo-frames tests still uses 'eth'-style naming in checks

[Vladimir Khlyunev]

ISO 263 (with enabled CentOS7)
Snapshot does not needed.

CI job failed https://product-ci.infra.mirantis.net/job/8.0.system_test.ubuntu.offloading/65/testReport/junit/%28root%29/offloading_neutron_vlan/offloading_neutron_vlan/

Root cause: after enabling CentOS7 with predictable interfaces naming schema we should avoid using hardcoded 'eth'-style naming

https://github.com/openstack/fuel-qa/blob/c468c7cc394e598838dbee774a11eea292d61a24/fuelweb_test/tests/test_offloading_types.py#L143
https://github.com/openstack/fuel-qa/blob/c468c7cc394e598838dbee774a11eea292d61a24/fuelweb_test/tests/test_jumbo_frames.py#L308
And so on

[OpenStack Infra (hudson-openstack)]

Change abandoned by Dmitriy Kruglov (<email address hidden>) on branch: master
Review: https://review.openstack.org/254812
Reason: No longer required due to https://review.openstack.org/#/c/255183 patch fixes the problem.

[Dmitriy Kruglov (dkruglov)]

The issue is fixed by the https://review.openstack.org/#/c/255183 patch.