mac80211: remove obsolete sentence from documentation

FIF_PROMISC_IN_BSS was removed in commit df140465
("mac80211: remove support for IFF_PROMISC").
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -2584,8 +2584,7 @@ void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb);
  *
  * @FIF_OTHER_BSS: pass frames destined to other BSSes
  *
- * @FIF_PSPOLL: pass PS Poll frames, if PROMISC_IN_BSS is not set then only
- * 	those addressed to this station.
+ * @FIF_PSPOLL: pass PS Poll frames
  *
  * @FIF_PROBE_REQ: pass probe request frames
  */