ASoC: rockchip: Add machine driver for max98090 codec

The driver is used for rockchip board using a max98090.

Reviewed-by: Dylan Reid <dgreid@chromium.org>
Signed-off-by: zhengxing <zhengxing@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/rockchip/Makefile b/sound/soc/rockchip/Makefile
index b921909..df3445b 100644
--- a/sound/soc/rockchip/Makefile
+++ b/sound/soc/rockchip/Makefile
@@ -2,3 +2,7 @@
 snd-soc-i2s-objs := rockchip_i2s.o
 
 obj-$(CONFIG_SND_SOC_ROCKCHIP_I2S) += snd-soc-i2s.o
+
+snd-soc-rockchip-max98090-objs := rockchip_max98090.o
+
+obj-$(CONFIG_SND_SOC_ROCKCHIP_MAX98090) += snd-soc-rockchip-max98090.o