mac80211: minstrel_ht: fix a logic error in RTS/CTS handling

RTS/CTS needs to be enabled if the rate is a fallback rate *or* if it's
a dual-stream rate and the sta is in dynamic SMPS mode.

Cc: stable@vger.kernel.org
Fixes: a3ebb4e1b763 ("mac80211: minstrel_ht: handle peers in dynamic SMPS")
Reported-by: Matías Richart <mrichart@fing.edu.uy>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/rc80211_minstrel_ht.c

@@ -872,7 +872,7 @@ minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
 	 *  - if station is in dynamic SMPS (and streams > 1)
 	 *  - for fallback rates, to increase chances of getting through
 	 */
-	if (offset > 0 &&
+	if (offset > 0 ||
 	    (mi->sta->smps_mode == IEEE80211_SMPS_DYNAMIC &&
 	     group->streams > 1)) {
 		ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts;