ASoC: tegra: Expose Headphones pin to userspace

So userspace can enable or disable it based on the current policy.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/tegra/tegra_max98090.c

@@ -136,6 +136,7 @@ static const struct snd_soc_dapm_widget tegra_max98090_dapm_widgets[] = {
 };
 
 static const struct snd_kcontrol_new tegra_max98090_controls[] = {
+	SOC_DAPM_PIN_SWITCH("Headphones"),
 	SOC_DAPM_PIN_SWITCH("Speakers"),
 };