mac80211: use eth_broadcast_addr

Instead of memset().

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --cc net/mac80211/cfg.c
Simple merge

diff --cc net/mac80211/ibss.c
Simple merge

diff --cc net/mac80211/mesh_pathtbl.c
Simple merge

diff --cc net/mac80211/tx.c
Simple merge