mac80211: introduce hw config change flags

This makes mac80211 notify the driver which configuration
actually changed, e.g. channel etc.

No driver changes, this is just plumbing, driver authors are
expected to act on this if they want to.

Also remove the HW CONFIG debug printk, it's incorrect, often
we configure something else.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 1359a37..8ec8f7e 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -997,7 +997,7 @@
 			    struct ieee80211_if_init_conf *conf);
 void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
 				struct ieee80211_if_init_conf *conf);
-int rt2x00mac_config(struct ieee80211_hw *hw, struct ieee80211_conf *conf);
+int rt2x00mac_config(struct ieee80211_hw *hw, u32 changed);
 int rt2x00mac_config_interface(struct ieee80211_hw *hw,
 			       struct ieee80211_vif *vif,
 			       struct ieee80211_if_conf *conf);