at86rf230: remove if branch

This patch removes an unnecessary if branch inside the tx complete
handler.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Reviewed-by: Stefan Schmidt <s.schmidt@samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/net/ieee802154/at86rf230.c

@@ -714,10 +714,7 @@ at86rf230_tx_complete(void *context)
 
 	enable_irq(lp->spi->irq);
 
-	if (lp->max_frame_retries <= 0)
-		ieee802154_xmit_complete(lp->hw, skb, true);
-	else
-		ieee802154_xmit_complete(lp->hw, skb, false);
+	ieee802154_xmit_complete(lp->hw, skb, !lp->tx_aret);
 }
 
 static void