mac80211: remove pointless 'params' NULL checks

These checks aren't necessary, cfg80211 never passes NULL.
Some static checkers complain about the missing checks on
the next line, but really the NULL checks are unnecessary.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/cfg.c

@@ -158,12 +158,10 @@ static int ieee80211_change_iface(struct wiphy *wiphy,
 	if (ret)
 		return ret;
 
-	if (type == NL80211_IFTYPE_AP_VLAN &&
-	    params && params->use_4addr == 0) {
+	if (type == NL80211_IFTYPE_AP_VLAN && params->use_4addr == 0) {
 		RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
 		ieee80211_check_fast_rx_iface(sdata);
-	} else if (type == NL80211_IFTYPE_STATION &&
-		   params && params->use_4addr >= 0) {
+	} else if (type == NL80211_IFTYPE_STATION && params->use_4addr >= 0) {
 		sdata->u.mgd.use_4addr = params->use_4addr;
 	}