ASoC: omap-mcpdm: Do not use platform_get_resource_byname() for DMA

The DMA resource no longer available via this API when booting with DT.
McPDM is only available on OMAP4/5 and both can boot with DT only.
Set the dma_data.filter_data to the DMA name which will be used by omap-pcm
to request the DMA channel.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/omap/omap-mcpdm.c b/sound/soc/omap/omap-mcpdm.c
index eb05c7e..a49dc52 100644
--- a/sound/soc/omap/omap-mcpdm.c
+++ b/sound/soc/omap/omap-mcpdm.c
@@ -66,7 +66,6 @@
 	bool restart;
 
 	struct snd_dmaengine_dai_dma_data dma_data[2];
-	unsigned int dma_req[2];
 };
 
 /*
@@ -477,19 +476,8 @@
 	mcpdm->dma_data[0].addr = res->start + MCPDM_REG_DN_DATA;
 	mcpdm->dma_data[1].addr = res->start + MCPDM_REG_UP_DATA;
 
-	res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "dn_link");
-	if (!res)
-		return -ENODEV;
-
-	mcpdm->dma_req[0] = res->start;
-	mcpdm->dma_data[0].filter_data = &mcpdm->dma_req[0];
-
-	res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "up_link");
-	if (!res)
-		return -ENODEV;
-
-	mcpdm->dma_req[1] = res->start;
-	mcpdm->dma_data[1].filter_data = &mcpdm->dma_req[1];
+	mcpdm->dma_data[0].filter_data = "dn_link";
+	mcpdm->dma_data[1].filter_data = "up_link";
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mpu");
 	if (res == NULL)