sound: Add a driver for max98088

This chip is used by spring. Add a driver for it and update the
samsung_sound driver to pick it up.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/sound/Makefile b/drivers/sound/Makefile
index d0bf51b..170e06a 100644
--- a/drivers/sound/Makefile
+++ b/drivers/sound/Makefile
@@ -12,5 +12,6 @@
 obj-$(CONFIG_I2S_ROCKCHIP)	+= rockchip_i2s.o rockchip_sound.o
 obj-$(CONFIG_I2S_SAMSUNG)	+= samsung_sound.o
 obj-$(CONFIG_SOUND_WM8994)	+= wm8994.o
+obj-$(CONFIG_SOUND_MAX98088)	+= max98088.o maxim_codec.o
 obj-$(CONFIG_SOUND_MAX98090)	+= max98090.o maxim_codec.o
 obj-$(CONFIG_SOUND_MAX98095)	+= max98095.o maxim_codec.o