IAVF_ITR_TX
iavf_wr(sc, I40E_VFINT_ITRN1(IAVF_ITR_TX, i), sc->sc_tx_itr);
iavf_wr(sc, I40E_VFINT_ITR01(IAVF_ITR_TX), sc->sc_tx_itr);
vec[num_vec].txitr_idx = htole16(IAVF_ITR_TX);
itr = IAVF_ITR_TX;