mac80211: add HE 6 GHz Band Capability element

Construct HE 6 GHz band capability element (IEEE 802.11ax/D6.0,
9.4.2.261) for association request and mesh beacon. The 6 GHz
capability information is passed by driver through iftypes caps.

Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Link: https://lore.kernel.org/r/1589399105-25472-7-git-send-email-rmanohar@codeaurora.org
[handle SMPS, adjust for previous patches, reserve SKB space properly,
 change to handle SKB directly]
Link: https://lore.kernel.org/r/20200528213443.643aa8101111.I3f9747c1147480f65445f13eda5c4a5ed4e86757@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index dac0166..344ea82 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -2177,6 +2177,8 @@ u8 ieee80211_ie_len_he_cap(struct ieee80211_sub_if_data *sdata, u8 iftype);
 u8 *ieee80211_ie_build_he_cap(u8 *pos,
 			      const struct ieee80211_sta_he_cap *he_cap,
 			      u8 *end);
+void ieee80211_ie_build_he_6ghz_cap(struct ieee80211_sub_if_data *sdata,
+				    struct sk_buff *skb);
 u8 *ieee80211_ie_build_he_oper(u8 *pos);
 int ieee80211_parse_bitrates(struct cfg80211_chan_def *chandef,
 			     const struct ieee80211_supported_band *sband,