iwlwifi: mvm: remove check for lq_sta in __iwl_mvm_rs_tx_status()

The check is not necessary anymore, because now the struct is not
allocated separately, but is part of the mvmsta struct.  Remove the
check, since it's dead code.
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/mvm/rs.c

@@ -3079,11 +3079,7 @@ static void __iwl_mvm_rs_tx_status(struct iwl_mvm *mvm,
 	struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
 	struct iwl_lq_sta *lq_sta = &mvmsta->lq_sta.rs_drv;
 
-	/* Treat uninitialized rate scaling data same as non-existing. */
-	if (!lq_sta) {
-		IWL_DEBUG_RATE(mvm, "Station rate scaling not created yet.\n");
-		return;
-	} else if (!lq_sta->pers.drv) {
+	if (!lq_sta->pers.drv) {
 		IWL_DEBUG_RATE(mvm, "Rate scaling not initialized yet.\n");
 		return;
 	}