mt76: mt7915 add ht mpdu density

set ht mpdu density to 4 usec.
Reviewed-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: MeiChia Chiu <MeiChia.Chiu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7915/init.c

@@ -369,15 +369,20 @@ mt7915_init_wiphy(struct ieee80211_hw *hw)
 
 	hw->max_tx_fragments = 4;
 
-	if (phy->mt76->cap.has_2ghz)
+	if (phy->mt76->cap.has_2ghz) {
 		phy->mt76->sband_2g.sband.ht_cap.cap |=
 			IEEE80211_HT_CAP_LDPC_CODING |
 			IEEE80211_HT_CAP_MAX_AMSDU;
+		phy->mt76->sband_2g.sband.ht_cap.ampdu_density =
+			IEEE80211_HT_MPDU_DENSITY_4;
+	}
 
 	if (phy->mt76->cap.has_5ghz) {
 		phy->mt76->sband_5g.sband.ht_cap.cap |=
 			IEEE80211_HT_CAP_LDPC_CODING |
 			IEEE80211_HT_CAP_MAX_AMSDU;
+		phy->mt76->sband_5g.sband.ht_cap.ampdu_density =
+			IEEE80211_HT_MPDU_DENSITY_4;
 
 		if (is_mt7915(&dev->mt76)) {
 			phy->mt76->sband_5g.sband.vht_cap.cap |=