mac80211: Process multicast RX registration for Action frames

Convert a user space registration for processing multicast Action frames
(NL80211_CMD_REGISTER_FRAME with NL80211_ATTR_RECEIVE_MULTICAST) to a
new enum ieee80211_filter_flags bit FIF_MCAST_ACTION so that drivers can
update their RX filter parameters appropriately, if needed.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20200421144815.19175-1-jouni@codeaurora.org
[rename variables to rx_mcast_action_reg indicating action frames only]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -1620,6 +1620,8 @@ enum ieee80211_vif_flags {
  *	monitor interface (if that is requested.)
  * @probe_req_reg: probe requests should be reported to mac80211 for this
  *	interface.
+ * @rx_mcast_action_reg: multicast Action frames should be reported to mac80211
+ *	for this interface.
  * @drv_priv: data area for driver use, will always be aligned to
  *	sizeof(void \*).
  * @txq: the multicast data TX queue (if driver uses the TXQ abstraction)
@@ -1648,6 +1650,7 @@ struct ieee80211_vif {
 #endif
 
 	bool probe_req_reg;
+	bool rx_mcast_action_reg;
 
 	bool txqs_stopped[IEEE80211_NUM_ACS];
 
@@ -3091,6 +3094,8 @@ void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb);
  * @FIF_PSPOLL: pass PS Poll frames
  *
  * @FIF_PROBE_REQ: pass probe request frames
+ *
+ * @FIF_MCAST_ACTION: pass multicast Action frames
  */
 enum ieee80211_filter_flags {
 	FIF_ALLMULTI		= 1<<1,
@@ -3101,6 +3106,7 @@ enum ieee80211_filter_flags {
 	FIF_OTHER_BSS		= 1<<6,
 	FIF_PSPOLL		= 1<<7,
 	FIF_PROBE_REQ		= 1<<8,
+	FIF_MCAST_ACTION	= 1<<9,
 };
 
 /**