nl80211: Export available antennas

Export the information which antennas are available for configuration as TX or
RX antennas via nl80211.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 8d2f5f8..9b62710 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -605,6 +605,11 @@
 	if (dev->wiphy.flags & WIPHY_FLAG_CONTROL_PORT_PROTOCOL)
 		NLA_PUT_FLAG(msg, NL80211_ATTR_CONTROL_PORT_ETHERTYPE);
 
+	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_ANTENNA_AVAIL_TX,
+		    dev->wiphy.available_antennas_tx);
+	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY_ANTENNA_AVAIL_RX,
+		    dev->wiphy.available_antennas_rx);
+
 	if ((dev->wiphy.available_antennas_tx ||
 	     dev->wiphy.available_antennas_rx) && dev->ops->get_antenna) {
 		u32 tx_ant = 0, rx_ant = 0;