bugfix: SRIOV used wrong device names

bugfix: SRIOV used wrong device names

QemuPciPassthrough class responsible for SRIOV testing
used wrong device names for GUEST configuration. Details
of HOST interfaces connected to the traffic generator were
used to initialize forwarding applications inside the guest.
Code was fixed to use correct device configuration.
As part of this fix, old bug in VNF type detection was fixed.

JIRA: VSPERF-389

Change-Id: I269c9232012980c600c171571e90beb11e7b72cd
Signed-off-by: Martin Klozik <martinx.klozik@intel.com>
Reviewed-by: Maryam Tahhan <maryam.tahhan@intel.com>
Reviewed-by: Al Morton <acmorton@att.com>
Reviewed-by: Christian Trautman <ctrautma@redhat.com>
Reviewed-by: Bill Michalowski <bmichalo@redhat.com>