ASoC: Add trivial pm_runtime usage to Samsung DAI drivers

Currently this won't actually do anything but using this will help the
core SoC code track when the system is idle.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/samsung/pcm.c b/sound/soc/samsung/pcm.c
index 5776add..56780206c 100644
--- a/sound/soc/samsung/pcm.c
+++ b/sound/soc/samsung/pcm.c
@@ -14,6 +14,7 @@
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/pm_runtime.h>
 
 #include <sound/soc.h>
 #include <sound/pcm_params.h>
@@ -580,6 +581,8 @@
 	pcm->dma_capture = &s3c_pcm_stereo_in[pdev->id];
 	pcm->dma_playback = &s3c_pcm_stereo_out[pdev->id];
 
+	pm_runtime_enable(&pdev->dev);
+
 	ret = snd_soc_register_dai(&pdev->dev, &s3c_pcm_dai[pdev->id]);
 	if (ret != 0) {
 		dev_err(&pdev->dev, "failed to get register DAI: %d\n", ret);
@@ -609,6 +612,8 @@
 
 	snd_soc_unregister_dai(&pdev->dev);
 
+	pm_runtime_disable(&pdev->dev);
+
 	iounmap(pcm->regs);
 
 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);