ath9k: Register larger listen interval

Notify the AP that we may be sleeping longer to allow the AP power
save code to buffer larger number of frames for us when using virtual
wiphys.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/main.c

@@ -1597,6 +1597,7 @@ void ath_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw)
 	hw->queues = 4;
 	hw->max_rates = 4;
 	hw->channel_change_time = 5000;
+	hw->max_listen_interval = 10;
 	hw->max_rate_tries = ATH_11N_TXMAXTRY;
 	hw->sta_data_size = sizeof(struct ath_node);
 	hw->vif_data_size = sizeof(struct ath_vif);