ASoC: core: Remove unused "n_widgets" field from snd_soc_dapm struct

Commit 497098be ("ASoC: dapm: Remove bodges for no-widget CODECs") removed the
last user of the n_widgets field. Currently it is incremented for each widget
added, but the value is never used, so we can remove it.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

include/sound/soc-dapm.h

@@ -565,7 +565,6 @@ struct snd_soc_dapm_update {
 
 /* DAPM context */
 struct snd_soc_dapm_context {
-	int n_widgets; /* number of widgets in this context */
 	enum snd_soc_bias_level bias_level;
 	enum snd_soc_bias_level suspend_bias_level;
 	struct delayed_work delayed_work;

sound/soc/soc-dapm.c

@@ -3123,7 +3123,6 @@ snd_soc_dapm_new_control(struct snd_soc_dapm_context *dapm,
 		break;
 	}
 
-	dapm->n_widgets++;
 	w->dapm = dapm;
 	w->codec = dapm->codec;
 	w->platform = dapm->platform;