mac80211: tdls: disentangle HT supported conditions

These conditions are rather difficult to follow, for example
because "!sta" only exists to not crash in the case that we
don't have a station pointer (WLAN_TDLS_SETUP_REQUEST) in
which the additional condition (peer supports HT) doesn't
actually matter anyway.

Cleaning this up only duplicates two lines of code but makes
the rest far easier to read, so do that.

As a side effect, smatch stops complaining about the lack of
a sta pointer test after the !sta (since the !sta goes away)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/tdls.c

@@ -345,24 +345,24 @@ ieee80211_tdls_add_setup_start_ies(struct ieee80211_sub_if_data *sdata,
 	 */
 	sband = local->hw.wiphy->bands[band];
 	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
-	if ((action_code == WLAN_TDLS_SETUP_REQUEST ||
-	     action_code == WLAN_TDLS_SETUP_RESPONSE) &&
-	    ht_cap.ht_supported && (!sta || sta->sta.ht_cap.ht_supported)) {
-		if (action_code == WLAN_TDLS_SETUP_REQUEST) {
-			ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 
-			/* disable SMPS in TDLS initiator */
-			ht_cap.cap |= (WLAN_HT_CAP_SM_PS_DISABLED
-				       << IEEE80211_HT_CAP_SM_PS_SHIFT);
-		} else {
-			/* disable SMPS in TDLS responder */
-			sta->sta.ht_cap.cap |=
-				(WLAN_HT_CAP_SM_PS_DISABLED
-				 << IEEE80211_HT_CAP_SM_PS_SHIFT);
+	if (action_code == WLAN_TDLS_SETUP_REQUEST && ht_cap.ht_supported) {
+		ieee80211_apply_htcap_overrides(sdata, &ht_cap);
 
-			/* the peer caps are already intersected with our own */
-			memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
-		}
+		/* disable SMPS in TDLS initiator */
+		ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
+				<< IEEE80211_HT_CAP_SM_PS_SHIFT;
+
+		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
+		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
+	} else if (action_code == WLAN_TDLS_SETUP_RESPONSE &&
+		   ht_cap.ht_supported && sta->sta.ht_cap.ht_supported) {
+		/* disable SMPS in TDLS responder */
+		sta->sta.ht_cap.cap |= WLAN_HT_CAP_SM_PS_DISABLED
+					<< IEEE80211_HT_CAP_SM_PS_SHIFT;
+
+		/* the peer caps are already intersected with our own */
+		memcpy(&ht_cap, &sta->sta.ht_cap, sizeof(ht_cap));
 
 		pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
 		ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);