wifi: ath11k: mac: fix struct ieee80211_sband_iftype_data handling

Commit e8c18412 ("wifi: cfg80211: annotate iftype_data pointer with
sparse") added sparse checks for struct ieee80211_sband_iftype_data handling
which immediately found an issue in ath11k:

drivers/net/wireless/ath/ath11k/mac.c:7952:22: warning: incorrect type in argument 1 (different address spaces)
drivers/net/wireless/ath/ath11k/mac.c:7952:22:    expected struct ieee80211_sta_he_cap const *he_cap
drivers/net/wireless/ath/ath11k/mac.c:7952:22:    got struct ieee80211_sta_he_cap const [noderef] __iftype_data *

The problem here is that we are accessing sband->iftype_data directly even
though we should use for_each_sband_iftype_data() or similar. Fortunately
there's ieee80211_get_he_iftype_cap_vif() which is just what we need here so
use it to get HE capabilities.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.23
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230927142708.2897504-2-kvalo@kernel.org

drivers/net/wireless/ath/ath11k/mac.c

@@ -7910,12 +7910,14 @@ ath11k_mac_get_tx_mcs_map(const struct ieee80211_sta_he_cap *he_cap)
 
 static bool
 ath11k_mac_bitrate_mask_get_single_nss(struct ath11k *ar,
+				       struct ath11k_vif *arvif,
 				       enum nl80211_band band,
 				       const struct cfg80211_bitrate_mask *mask,
 				       int *nss)
 {
 	struct ieee80211_supported_band *sband = &ar->mac.sbands[band];
 	u16 vht_mcs_map = le16_to_cpu(sband->vht_cap.vht_mcs.tx_mcs_map);
+	const struct ieee80211_sta_he_cap *he_cap;
 	u16 he_mcs_map = 0;
 	u8 ht_nss_mask = 0;
 	u8 vht_nss_mask = 0;
@@ -7946,7 +7948,11 @@ ath11k_mac_bitrate_mask_get_single_nss(struct ath11k *ar,
 			return false;
 	}
 
-	he_mcs_map = le16_to_cpu(ath11k_mac_get_tx_mcs_map(&sband->iftype_data->he_cap));
+	he_cap = ieee80211_get_he_iftype_cap_vif(sband, arvif->vif);
+	if (!he_cap)
+		return false;
+
+	he_mcs_map = le16_to_cpu(ath11k_mac_get_tx_mcs_map(he_cap));
 
 	for (i = 0; i < ARRAY_SIZE(mask->control[band].he_mcs); i++) {
 		if (mask->control[band].he_mcs[i] == 0)
@@ -8362,7 +8368,7 @@ ath11k_mac_op_set_bitrate_mask(struct ieee80211_hw *hw,
 		ieee80211_iterate_stations_atomic(ar->hw,
 						  ath11k_mac_disable_peer_fixed_rate,
 						  arvif);
-	} else if (ath11k_mac_bitrate_mask_get_single_nss(ar, band, mask,
+	} else if (ath11k_mac_bitrate_mask_get_single_nss(ar, arvif, band, mask,
 							  &single_nss)) {
 		rate = WMI_FIXED_RATE_NONE;
 		nss = single_nss;