wireless: Use eth_<foo>_addr instead of memset

Use the built-in function instead of memset.

Miscellanea:

Add #include <linux/etherdevice.h> where appropriate
Use ETH_ALEN instead of 6

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wireless/ath/ath5k/base.c

@@ -528,7 +528,7 @@ ath5k_update_bssid_mask_and_opmode(struct ath5k_hw *ah,
 	 * together with the BSSID mask when matching addresses.
 	 */
 	iter_data.hw_macaddr = common->macaddr;
-	memset(&iter_data.mask, 0xff, ETH_ALEN);
+	eth_broadcast_addr(iter_data.mask);
 	iter_data.found_active = false;
 	iter_data.need_set_hw_addr = true;
 	iter_data.opmode = NL80211_IFTYPE_UNSPECIFIED;