IEEE80211_ERP_USE_PROTECTION
prot |= IEEE80211_ERP_USE_PROTECTION;
erp |= IEEE80211_ERP_USE_PROTECTION;
(ni->ni_erp & IEEE80211_ERP_USE_PROTECTION))
(ni->ni_erp & IEEE80211_ERP_USE_PROTECTION))
(erp & IEEE80211_ERP_USE_PROTECTION))
(ni->ni_erp & IEEE80211_ERP_USE_PROTECTION))
erp |= IEEE80211_ERP_USE_PROTECTION;