ath5k: claim support for IBSS RSN

Disable group keys programming when using IBSS RSN. Keys will be managed using
software. In this way IBSS RSN can correctly work.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index d366dad..4ab835f 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -2442,6 +2442,9 @@
 		BIT(NL80211_IFTYPE_ADHOC) |
 		BIT(NL80211_IFTYPE_MESH_POINT);
 
+	/* SW support for IBSS_RSN is provided by mac80211 */
+	hw->wiphy->flags |= WIPHY_FLAG_IBSS_RSN;
+
 	/* both antennas can be configured as RX or TX */
 	hw->wiphy->available_antennas_tx = 0x3;
 	hw->wiphy->available_antennas_rx = 0x3;