mt76: mt7915: send EAPOL frames at lowest rate

The firmware rate control may choose the high rate for EAPOL frames,
so checking IEEE80211_TX_CTL_USE_MINRATE to use the lowest TX rate.
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -948,7 +948,8 @@ mt7915_mac_write_txwi_80211(struct mt7915_dev *dev, __le32 *txwi,
 		txwi[3] &= ~cpu_to_le32(MT_TXD3_PROTECT_FRAME);
 	}
 
-	if (!ieee80211_is_data(fc) || multicast)
+	if (!ieee80211_is_data(fc) || multicast ||
+	    info->flags & IEEE80211_TX_CTL_USE_MINRATE)
 		val |= MT_TXD2_FIX_RATE;
 
 	txwi[2] |= cpu_to_le32(val);