wifi: mt76: mt7996: fix ldpc setting

The non-AP interfaces would not use conf->vht_ldpc so they never set
STA_CAP_VHT_LDPC even if peer-station support LDPC.
Check conf->vht_ldpc only for AP interface.

Without this patch, station only uses BCC to transmit packet in VHT mode.

Fixes: dda423d ("wifi: mt76: mt7996: remove mt7996_mcu_beacon_check_caps()")
Signed-off-by: Peter Chiu <[email protected]>
Signed-off-by: Shayne Chen <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Felix Fietkau <[email protected]>

Author: Peter Chiu

drivers/net/wireless/mediatek/mt76/mt7996/mcu.c

@@ -2066,7 +2066,7 @@ mt7996_mcu_sta_rate_ctrl_tlv(struct sk_buff *skb, struct mt7996_dev *dev,
 			cap |= STA_CAP_VHT_TX_STBC;
 		if (sta->deflink.vht_cap.cap & IEEE80211_VHT_CAP_RXSTBC_1)
 			cap |= STA_CAP_VHT_RX_STBC;
-		if (vif->bss_conf.vht_ldpc &&
+		if ((vif->type != NL80211_IFTYPE_AP || vif->bss_conf.vht_ldpc) &&
 		    (sta->deflink.vht_cap.cap & IEEE80211_VHT_CAP_RXLDPC))
 			cap |= STA_CAP_VHT_LDPC;