dma: mmp_pdma: add missing platform_set_drvdata() in mmp_pdma_probe()

Add missing platform_set_drvdata() in mmp_pdma_probe(), otherwise
calling platform_get_drvdata() in mmp_pdma_remove() returns NULL.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

drivers/dma/mmp_pdma.c

@@ -1017,6 +1017,7 @@ static int mmp_pdma_probe(struct platform_device *op)
 		}
 	}
 
+	platform_set_drvdata(op, pdev);
 	dev_info(pdev->device.dev, "initialized %d channels\n", dma_channels);
 	return 0;
 }