mac80211: Fix dropping broadcast packets in 802.11 encap

Broadcast pkts like arp are getting dropped in 'ieee80211_8023_xmit'.
Fix this by replacing is_valid_ether_addr api with is_zero_ether_addr.

Fixes: 50ff477a ("mac80211: add 802.11 encapsulation offloading support")
Signed-off-by: NSeevalamuthu Mariappan <seevalam@codeaurora.org>
Link: https://lore.kernel.org/r/1591697754-4975-1-git-send-email-seevalam@codeaurora.orgSigned-off-by: NJohannes Berg <johannes.berg@intel.com>

net/mac80211/tx.c

@@ -4206,7 +4206,7 @@ static void ieee80211_8023_xmit(struct ieee80211_sub_if_data *sdata,
 	    (!sta || !test_sta_flag(sta, WLAN_STA_TDLS_PEER)))
 		ra = sdata->u.mgd.bssid;
 
-	if (!is_valid_ether_addr(ra))
+	if (is_zero_ether_addr(ra))
 		goto out_free;
 
 	multicast = is_multicast_ether_addr(ra);