dmaengine: at_xdmac: Replace two if statements with only one with two conditions

Add a cosmetic change and replace two if statements with a single if
statement with two conditions. In case the optional txstate parameter is
NULL, we return the dma_cookie_status, which is fine, no functional change
required.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/r/20220802140630.243550-1-tudor.ambarus@microchip.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/at_xdmac.c

@@ -1470,10 +1470,7 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
 	bool			initd;
 
 	ret = dma_cookie_status(chan, cookie, txstate);
-	if (ret == DMA_COMPLETE)
-		return ret;
-
-	if (!txstate)
+	if (ret == DMA_COMPLETE || !txstate)
 		return ret;
 
 	spin_lock_irqsave(&atchan->lock, flags);