ASoC: Add indirection for CODEC private data

One of the features of the multi CODEC work is that it embeds a struct
device in the CODEC to provide diagnostics via a sysfs class rather than
via the device tree, at which point it's much better to use the struct
device private data rather than having two places to store it. Provide
an accessor function to allow this change to be made more easily, and
update all the CODEC drivers are updated.

To ensure use of the accessor the private data structure member is
renamed, meaning that if code developed with older an older core that
still uses private_data is merged it will fail to build.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/sound/soc/codecs/wm8750.c b/sound/soc/codecs/wm8750.c
index 4bbc512..60d7cf8 100644
--- a/sound/soc/codecs/wm8750.c
+++ b/sound/soc/codecs/wm8750.c
@@ -482,7 +482,7 @@
 		int clk_id, unsigned int freq, int dir)
 {
 	struct snd_soc_codec *codec = codec_dai->codec;
-	struct wm8750_priv *wm8750 = codec->private_data;
+	struct wm8750_priv *wm8750 = snd_soc_codec_get_drvdata(codec);
 
 	switch (freq) {
 	case 11289600:
@@ -561,7 +561,7 @@
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 	struct snd_soc_device *socdev = rtd->socdev;
 	struct snd_soc_codec *codec = socdev->card->codec;
-	struct wm8750_priv *wm8750 = codec->private_data;
+	struct wm8750_priv *wm8750 = snd_soc_codec_get_drvdata(codec);
 	u16 iface = snd_soc_read(codec, WM8750_IFACE) & 0x1f3;
 	u16 srate = snd_soc_read(codec, WM8750_SRATE) & 0x1c0;
 	int coeff = get_coeff(wm8750->sysclk, params_rate(params));
@@ -775,10 +775,9 @@
 	codec->set_bias_level = wm8750_set_bias_level;
 	codec->dai = &wm8750_dai;
 	codec->num_dai = 1;
-	codec->private_data = wm8750;
 	codec->reg_cache_size = ARRAY_SIZE(wm8750->reg_cache) + 1;
 	codec->reg_cache = &wm8750->reg_cache;
-	codec->private_data = wm8750;
+	snd_soc_codec_set_drvdata(codec, wm8750);
 
 	memcpy(codec->reg_cache, wm8750_reg, sizeof(wm8750->reg_cache));