spi: fsl-lpspi: Use dma_request_chan() directly for channel request

dma_request_slave_channel_reason() is:
#define dma_request_slave_channel_reason(dev, name) \
	dma_request_chan(dev, name)
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191113094256.1108-4-peter.ujfalusi@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-fsl-lpspi.c

@@ -675,7 +675,7 @@ static int fsl_lpspi_dma_init(struct device *dev,
 	int ret;
 
 	/* Prepare for TX DMA: */
-	controller->dma_tx = dma_request_slave_channel_reason(dev, "tx");
+	controller->dma_tx = dma_request_chan(dev, "tx");
 	if (IS_ERR(controller->dma_tx)) {
 		ret = PTR_ERR(controller->dma_tx);
 		dev_dbg(dev, "can't get the TX DMA channel, error %d!\n", ret);
@@ -684,7 +684,7 @@ static int fsl_lpspi_dma_init(struct device *dev,
 	}
 
 	/* Prepare for RX DMA: */
-	controller->dma_rx = dma_request_slave_channel_reason(dev, "rx");
+	controller->dma_rx = dma_request_chan(dev, "rx");
 	if (IS_ERR(controller->dma_rx)) {
 		ret = PTR_ERR(controller->dma_rx);
 		dev_dbg(dev, "can't get the RX DMA channel, error %d\n", ret);