ASoC: rt5682: remove useless assignments

cppcheck warnings:

sound/soc/codecs/rt5682.c:1234:6: style: Redundant initialization for
'idx'. The initialized value is overwritten before it is
read. [redundantInitialization]
 idx = rt5682_div_sel(rt5682, dmic_clk_rate, div, ARRAY_SIZE(div));
     ^
sound/soc/codecs/rt5682.c:1228:10: note: idx is initialized
 int idx = -EINVAL, dmic_clk_rate = 3072000;
         ^
sound/soc/codecs/rt5682.c:1234:6: note: idx is overwritten
 idx = rt5682_div_sel(rt5682, dmic_clk_rate, div, ARRAY_SIZE(div));
     ^

sound/soc/codecs/rt5682.c:1263:6: style: Redundant initialization for
'idx'. The initialized value is overwritten before it is
read. [redundantInitialization]
 idx = rt5682_div_sel(rt5682, ref, div_f, ARRAY_SIZE(div_f));
     ^
sound/soc/codecs/rt5682.c:1248:25: note: idx is initialized
 int ref, val, reg, idx = -EINVAL;
                        ^
sound/soc/codecs/rt5682.c:1263:6: note: idx is overwritten
 idx = rt5682_div_sel(rt5682, ref, div_f, ARRAY_SIZE(div_f));
     ^
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210302212527.55158-24-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt5682.c

@@ -1225,7 +1225,7 @@ static int set_dmic_clk(struct snd_soc_dapm_widget *w,
 	struct snd_soc_component *component =
 		snd_soc_dapm_to_component(w->dapm);
 	struct rt5682_priv *rt5682 = snd_soc_component_get_drvdata(component);
-	int idx = -EINVAL, dmic_clk_rate = 3072000;
+	int idx, dmic_clk_rate = 3072000;
 	static const int div[] = {2, 4, 6, 8, 12, 16, 24, 32, 48, 64, 96, 128};
 
 	if (rt5682->pdata.dmic_clk_rate)
@@ -1245,7 +1245,7 @@ static int set_filter_clk(struct snd_soc_dapm_widget *w,
 	struct snd_soc_component *component =
 		snd_soc_dapm_to_component(w->dapm);
 	struct rt5682_priv *rt5682 = snd_soc_component_get_drvdata(component);
-	int ref, val, reg, idx = -EINVAL;
+	int ref, val, reg, idx;
 	static const int div_f[] = {1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48};
 	static const int div_o[] = {1, 2, 4, 6, 8, 12, 16, 24, 32, 48};