dm: sound: Complete migration to driver model

All users of sound are converted to use driver model. Drop the old code
and the CONFIG_DM_SOUND option.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/sound/Makefile b/drivers/sound/Makefile
index 937df15..1de4346 100644
--- a/drivers/sound/Makefile
+++ b/drivers/sound/Makefile
@@ -4,16 +4,12 @@
 # R. Chandrasekar <rcsekar@samsung.com>
 
 obj-$(CONFIG_SOUND)	+= sound.o
-obj-$(CONFIG_DM_SOUND)	+= codec-uclass.o
-obj-$(CONFIG_DM_SOUND)	+= i2s-uclass.o
-obj-$(CONFIG_DM_SOUND)	+= sound-uclass.o
+obj-$(CONFIG_SOUND)	+= codec-uclass.o
+obj-$(CONFIG_SOUND)	+= i2s-uclass.o
+obj-$(CONFIG_SOUND)	+= sound-uclass.o
 obj-$(CONFIG_I2S_SAMSUNG)	+= samsung-i2s.o
 obj-$(CONFIG_SOUND_SANDBOX)	+= sandbox.o
-ifdef CONFIG_DM_SOUND
 obj-$(CONFIG_I2S_SAMSUNG)	+= samsung_sound.o
-else
-obj-$(CONFIG_I2S)	+= sound-i2s.o
-endif
 obj-$(CONFIG_SOUND_WM8994)	+= wm8994.o
 obj-$(CONFIG_SOUND_MAX98090)	+= max98090.o maxim_codec.o
 obj-$(CONFIG_SOUND_MAX98095)	+= max98095.o maxim_codec.o