rt2x00: Implement get_survey callback for rt2800

Implement the get_survey callback to allow user space to read statistics
about the current channel condition.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2800lib.h b/drivers/net/wireless/rt2x00/rt2800lib.h
index 81cbc92..e3c995a 100644
--- a/drivers/net/wireless/rt2x00/rt2800lib.h
+++ b/drivers/net/wireless/rt2x00/rt2800lib.h
@@ -199,5 +199,7 @@
 int rt2800_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 			enum ieee80211_ampdu_mlme_action action,
 			struct ieee80211_sta *sta, u16 tid, u16 *ssn);
+int rt2800_get_survey(struct ieee80211_hw *hw, int idx,
+		      struct survey_info *survey);
 
 #endif /* RT2800LIB_H */