ath5k: temporarily disable crypto for AP mode

Pavel Roskin reported some issues with using AP mode without
nohwcrypt=1.  Most likely this is similar to the problem fixed
some time ago in ath9k by 3f53dd64,
"ath9k: Fix hw crypto configuration for TKIP in AP mode."

That only affects TKIP but it's easiest to just disable that and
WEP too until we get a proper fix in.
Signed-off-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

@@ -2970,6 +2970,9 @@ ath5k_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	if (modparam_nohwcrypt)
 		return -EOPNOTSUPP;
 
+	if (sc->opmode == NL80211_IFTYPE_AP)
+		return -EOPNOTSUPP;
+
 	switch (key->alg) {
 	case ALG_WEP:
 	case ALG_TKIP: