mac80211: clean up beacon interval settings

We currently have two beacon interval configuration knobs:
hw.conf.beacon_int and vif.bss_info.beacon_int. This is
rather confusing, even though the former is used when we
beacon ourselves and the latter when we are associated to
an AP.

This just deprecates the hw.conf.beacon_int setting in favour
of always using vif.bss_info.beacon_int. Since it touches all
the beaconing IBSS code anyway, we can also add support for
the cfg80211 IBSS beacon interval configuration easily.

NOTE: The hw.conf.beacon_int setting is retained for now due
      to drivers still using it -- I couldn't untangle all
      drivers, some are updated in this patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/b43legacy/main.c b/drivers/net/wireless/b43legacy/main.c
index ee202b4..276f314 100644
--- a/drivers/net/wireless/b43legacy/main.c
+++ b/drivers/net/wireless/b43legacy/main.c
@@ -2721,11 +2721,6 @@
 	/* Antennas for RX and management frame TX. */
 	b43legacy_mgmtframe_txantenna(dev, antenna_tx);
 
-	/* Update templates for AP mode. */
-	if (b43legacy_is_mode(wl, NL80211_IFTYPE_AP))
-		b43legacy_set_beacon_int(dev, conf->beacon_int);
-
-
 	if (!!conf->radio_enabled != phy->radio_on) {
 		if (conf->radio_enabled) {
 			b43legacy_radio_turn_on(dev);
@@ -2827,6 +2822,11 @@
 
 	b43legacy_mac_suspend(dev);
 
+	if (changed & BSS_CHANGED_BEACON_INT &&
+	    (b43legacy_is_mode(wl, NL80211_IFTYPE_AP) ||
+	     b43legacy_is_mode(wl, NL80211_IFTYPE_ADHOC)))
+		b43legacy_set_beacon_int(dev, conf->beacon_int);
+
 	if (changed & BSS_CHANGED_BASIC_RATES)
 		b43legacy_update_basic_rates(dev, conf->basic_rates);