mt76x0: trim rx skb to proper length

We need to truncate skb to proper length. This fix below message:

wlan0: associating with AP with corrupt beacon and probe response

Fixes: 9d87d9fad47e ("mt76x0: unify tx/rx datapath with mt76x2u driver")
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NFelix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76x0/mac.c

@@ -236,6 +236,7 @@ u32 mt76x0_mac_process_rx(struct mt76x0_dev *dev, struct sk_buff *skb,
 
 	mt76x02_remove_hdr_pad(skb, pad_len);
 
+	pskb_trim(skb, len);
 	status->chains = BIT(0);
 	rssi = mt76x0_phy_get_rssi(dev, rxwi);
 	status->chain_signal[0] = status->signal = rssi;