mac80211: Don't merge if BSSID is set manually

If you set a fixed BSSID manually, you never want that the driver
change it back, or your ad-hoc mesh network will break into peaces. So
don't do it.

Signed-off-by: Alina Friedrichsen <x-alina@gmx.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 563ceb4..2db5660 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1644,6 +1644,7 @@
 
 	/* check if we need to merge IBSS */
 	if (sdata->vif.type == NL80211_IFTYPE_ADHOC && beacon &&
+	    (!(sdata->u.sta.flags & IEEE80211_STA_BSSID_SET)) &&
 	    bss->capability & WLAN_CAPABILITY_IBSS &&
 	    bss->freq == local->oper_channel->center_freq &&
 	    elems->ssid_len == sdata->u.sta.ssid_len &&