ASoC: add snd_soc_component_read32

Current codec drivers are using snd_soc_read(). It will be replaced
into snd_soc_component_read(), but these 2 are using different style.
For example, it will be

	- val = snd_soc_read(xxx, reg);
	+ ret = snd_soc_component_read(xxx, reg, &val);
	+ if (ret < 0) {
	+	...
	+ }

To more smooth replace, let's add snd_soc_component_read32
which is copied from snd_soc_read()

	- val = snd_soc_read(xxx, reg);
	+ val = snd_soc_component_read32(xxx, reg);

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/include/sound/soc.h b/include/sound/soc.h
index 6c80852..7475882 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -1498,6 +1498,8 @@
 /* component IO */
 int snd_soc_component_read(struct snd_soc_component *component,
 	unsigned int reg, unsigned int *val);
+unsigned int snd_soc_component_read32(struct snd_soc_component *component,
+				      unsigned int reg);
 int snd_soc_component_write(struct snd_soc_component *component,
 	unsigned int reg, unsigned int val);
 int snd_soc_component_update_bits(struct snd_soc_component *component,