nl80211: Fix a GET_KEY reply attribute

Use the NL80211_KEY_IDX attribute inside the NL80211_ATTR_KEY in
NL80211_CMD_GET_KEY responses to comply with nl80211_key_policy.
This is unlikely to affect existing userspace.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/nl80211.c

@@ -3351,7 +3351,7 @@ static void get_key_callback(void *c, struct key_params *params)
 			 params->cipher)))
 		goto nla_put_failure;
 
-	if (nla_put_u8(cookie->msg, NL80211_ATTR_KEY_IDX, cookie->idx))
+	if (nla_put_u8(cookie->msg, NL80211_KEY_IDX, cookie->idx))
 		goto nla_put_failure;
 
 	nla_nest_end(cookie->msg, key);