libertas: get current channel out of priv->curbssparams

... as priv->curbssparams won't exist once libertas+cfg80211 lands.

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/libertas/dev.h b/drivers/net/wireless/libertas/dev.h
index 27f0f1f..1a67511 100644
--- a/drivers/net/wireless/libertas/dev.h
+++ b/drivers/net/wireless/libertas/dev.h
@@ -165,6 +165,7 @@
 	/* NIC/link operation characteristics */
 	u16 mac_control;
 	u8 radio_on;
+	u8 channel;
 	s16 txpower_cur;
 	s16 txpower_min;
 	s16 txpower_max;