mxs: remove obsolete kernel package depending on linux 3.18

Signed-off-by: Felix Fietkau <nbd@nbd.name>

target/linux/mxs/modules.mk

@@ -33,27 +33,6 @@ endef
 
 $(eval $(call KernelPackage,wdt-stmp3xxx))
 
-define KernelPackage/sound-soc-mxs
-  TITLE:=Freescale i.MX23/i.MX28 built-in SoC sound support
-  KCONFIG:= \
-	CONFIG_SND_SOC_MXS_BUILTIN_CODEC \
-	CONFIG_SND_MXS_SOC_BUILTIN
-  FILES:= \
-	$(LINUX_DIR)/sound/soc/mxs/snd-soc-mxs-builtin-audio.ko \
-	$(LINUX_DIR)/sound/soc/mxs/snd-soc-mxs-builtin-dai.ko \
-	$(LINUX_DIR)/sound/soc/mxs/snd-soc-mxs-builtin-pcm.ko \
-	$(LINUX_DIR)/sound/soc/codecs/snd-soc-mxs-builtin-codec.ko
-  AUTOLOAD:=$(call AutoLoad,65,snd-soc-mxs-builtin-pcm snd-soc-mxs-builtin-dai snd-soc-mxs-builtin-codec snd-soc-mxs-builtin-audio)
-  DEPENDS:=@TARGET_mxs +kmod-sound-soc-core @LINUX_3_18
-  $(call AddDepends/sound)
-endef
-
-define KernelPackage/sound-soc-mxs/description
-  Kernel support for Freescale i.MX23/i.MX28 built-in SoC audio
-endef
-
-$(eval $(call KernelPackage,sound-soc-mxs))
-
 define KernelPackage/iio-mxs-lradc
   SUBMENU:=$(OTHER_MENU)
   TITLE:=Freescale i.MX23/28 LRADC driver