mac80211: recalc min_def chanctx even when chandef is identical

The min_def chanctx is affected not only by the current chandef, but
sometimes also by other stations on the vif. There's a valid scenario
where a TDLS peer can widen its BW, thereby causing the min_def
to increase.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/chan.c

@@ -343,8 +343,10 @@ static void ieee80211_change_chanctx(struct ieee80211_local *local,
 				     struct ieee80211_chanctx *ctx,
 				     const struct cfg80211_chan_def *chandef)
 {
-	if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
+	if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) {
+		ieee80211_recalc_chanctx_min_def(local, ctx);
 		return;
+	}
 
 	WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));