wifi: mac80211: fix flow dissection for forwarded packets

Adjust the network header to point at the correct payload offset

Fixes: 986e43b19a ("wifi: mac80211: fix receiving A-MSDU frames on mesh interfaces")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20230324120924.38412-2-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/rx.c

@@ -2850,7 +2850,7 @@ ieee80211_rx_mesh_data(struct ieee80211_sub_if_data *sdata, struct sta_info *sta
 		hdrlen += ETH_ALEN;
 	else
 		fwd_skb->protocol = htons(fwd_skb->len - hdrlen);
-	skb_set_network_header(fwd_skb, hdrlen);
+	skb_set_network_header(fwd_skb, hdrlen + 2);
 
 	info = IEEE80211_SKB_CB(fwd_skb);
 	memset(info, 0, sizeof(*info));