NL80211_TXRATE_FORCE_SGI
arvif->bitrate_mask.control[i].gi = NL80211_TXRATE_FORCE_SGI;
if (sgi == NL80211_TXRATE_FORCE_SGI) {
gi = (_he) ? gi : gi == NL80211_TXRATE_FORCE_SGI; \
gi = (_he) ? gi : gi == NL80211_TXRATE_FORCE_SGI; \