ASoC: zx: Add zx296702 SPDIF support

Add driver for zx296702 SPDIF controller

Signed-off-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/Makefile b/sound/soc/Makefile
index 974ba70..57bf32d 100644
--- a/sound/soc/Makefile
+++ b/sound/soc/Makefile
@@ -38,3 +38,4 @@
 obj-$(CONFIG_SND_SOC)	+= txx9/
 obj-$(CONFIG_SND_SOC)	+= ux500/
 obj-$(CONFIG_SND_SOC)	+= xtensa/
+obj-$(CONFIG_SND_SOC)	+= zte/