Use 'first_vf_id' and the 'vf_id' that is input as part of adding
a representor to obtain the PCI function ID(FID) of the VF(VFR endpoint).
Use the FID as an input to FUNC_QCFG HWRM cmd to obtain the default
vnic ID of the VF.
Along with getting the default vNIC ID by supplying the FW FID of
the VF-rep endpoint to HWRM_FUNC_QCFG, obtain and store it's
function svif.