mac80211: remove some unused code

There are a number of unused variables that gcc
pointed out (when building with W=1) as well as
some conditions that can never be true due to
the datatypes used: unsigned values can't be
less than zero. Remove this code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -2823,7 +2823,6 @@ static int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_tx_info *info;
 	struct sk_buff *skb = NULL;
 	bool send_direct;
 	int ret;
@@ -2849,7 +2848,6 @@ static int ieee80211_tdls_mgmt(struct wiphy *wiphy, struct net_device *dev,
 	if (!skb)
 		return -ENOMEM;
 
-	info = IEEE80211_SKB_CB(skb);
 	skb_reserve(skb, local->hw.extra_tx_headroom);
 
 	switch (action_code) {

net/mac80211/mlme.c

@@ -2617,14 +2617,9 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
 
 
 	if (elems.ht_cap_elem && elems.ht_operation && elems.wmm_param &&
-	    !(ifmgd->flags & IEEE80211_STA_DISABLE_11N)) {
-		struct ieee80211_supported_band *sband;
-
-		sband = local->hw.wiphy->bands[chan->band];
-
+	    !(ifmgd->flags & IEEE80211_STA_DISABLE_11N))
 		changed |= ieee80211_config_ht_tx(sdata, elems.ht_operation,
 						  bssid, true);
-	}
 
 	if (elems.country_elem && elems.pwr_constr_elem &&
 	    mgmt->u.probe_resp.capab_info &

net/mac80211/rx.c

@@ -1384,9 +1384,7 @@ ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
 			 struct sk_buff **skb)
 {
 	struct ieee80211_fragment_entry *entry;
-	int idx;
 
-	idx = sdata->fragment_next;
 	entry = &sdata->fragments[sdata->fragment_next++];
 	if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
 		sdata->fragment_next = 0;
@@ -3010,8 +3008,7 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
 
 	WARN_ON_ONCE(softirq_count() == 0);
 
-	if (WARN_ON(status->band < 0 ||
-		    status->band >= IEEE80211_NUM_BANDS))
+	if (WARN_ON(status->band >= IEEE80211_NUM_BANDS))
 		goto drop;
 
 	sband = local->hw.wiphy->bands[status->band];
@@ -3056,8 +3053,7 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
 			 * hardware error. The driver should catch hardware
 			 * errors.
 			 */
-			if (WARN((status->rate_idx < 0 ||
-				 status->rate_idx > 76),
+			if (WARN(status->rate_idx > 76,
 				 "Rate marked as an HT rate but passed "
 				 "status->rate_idx is not "
 				 "an MCS index [0-76]: %d (0x%02x)\n",
@@ -3065,8 +3061,7 @@ void ieee80211_rx(struct ieee80211_hw *hw, struct sk_buff *skb)
 				 status->rate_idx))
 				goto drop;
 		} else {
-			if (WARN_ON(status->rate_idx < 0 ||
-				    status->rate_idx >= sband->n_bitrates))
+			if (WARN_ON(status->rate_idx >= sband->n_bitrates))
 				goto drop;
 			rate = &sband->bitrates[status->rate_idx];
 		}

net/mac80211/tx.c

@@ -944,7 +944,6 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
 	fragnum = 0;
 
 	skb_queue_walk(&tx->skbs, skb) {
-		int next_len;
 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
 
 		hdr = (void *)skb->data;
@@ -963,7 +962,6 @@ ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
 		} else {
 			hdr->frame_control &= ~morefrags;
-			next_len = 0;
 		}
 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
 		fragnum++;