ASoC: use snd_soc_component_init_regmap() on si476x

To setup regmap, ALSA SoC has snd_soc_component_init_regmap() and
.get_regmap. But these are duplicated feature.
Let's use snd_soc_component_init_regmap() and remove .get_regmap
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/si476x.c

@@ -231,14 +231,17 @@ static struct snd_soc_dai_driver si476x_dai = {
 	.ops		= &si476x_dai_ops,
 };
 
-static struct regmap *si476x_get_regmap(struct device *dev)
+static int si476x_probe(struct snd_soc_component *component)
 {
-	return dev_get_regmap(dev->parent, NULL);
+	snd_soc_component_init_regmap(component,
+				dev_get_regmap(component->dev->parent, NULL));
+
+	return 0;
 }
 
 static const struct snd_soc_codec_driver soc_codec_dev_si476x = {
-	.get_regmap = si476x_get_regmap,
 	.component_driver = {
+		.probe			= si476x_probe,
 		.dapm_widgets		= si476x_dapm_widgets,
 		.num_dapm_widgets	= ARRAY_SIZE(si476x_dapm_widgets),
 		.dapm_routes		= si476x_dapm_routes,