mac80211: Add antenna configuration

Allow antenna configuration by calling driver's function for it.

We disallow antenna configuration if the wiphy is already running, mainly to
make life easier for 802.11n drivers which need to recalculate HT capabilites.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 6122e8a..a7323ec 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1799,6 +1799,8 @@
 	void (*channel_switch)(struct ieee80211_hw *hw,
 			       struct ieee80211_channel_switch *ch_switch);
 	int (*napi_poll)(struct ieee80211_hw *hw, int budget);
+	int (*set_antenna)(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant);
+	int (*get_antenna)(struct ieee80211_hw *hw, u32 *tx_ant, u32 *rx_ant);
 };
 
 /**