drm/bridge: sii902x: Select SND_SOC_HDMI_CODEC if SND_SOC is configured

To enable HDMI audio the SND_SOC_HDMI_CODEC needs to be
configured. Enable HDMI audio by selecting SND_SOC_HDMI_CODEC if
SND_SOC is configured. SND_SOC_HDMI_CODEC has no config menu entry and
should be selected automatically by the drivers using it.
Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
[narmstrong: atomatically -> automatically]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191129152342.29145-1-jsarha@ti.com

drivers/gpu/drm/bridge/Kconfig

@@ -98,6 +98,7 @@ config DRM_SII902X
 	select DRM_KMS_HELPER
 	select REGMAP_I2C
 	select I2C_MUX
+	select SND_SOC_HDMI_CODEC if SND_SOC
 	---help---
 	  Silicon Image sii902x bridge chip driver.