kernel: kmod-isdn4linux: Remove package

The isdn4linux drivers and subsystem was removed in kernel 5.3, remove
the kernel package also from OpenWrt.

Signed-off-by: Hauke Mehrtens <[email protected]>

package/kernel/linux/modules/netsupport.mk

@@ -163,38 +163,6 @@ endef
 $(eval $(call KernelPackage,misdn))
 
 
-define KernelPackage/isdn4linux
-  SUBMENU:=$(NETWORK_SUPPORT_MENU)
-  TITLE:=Old ISDN4Linux (deprecated)
-  DEPENDS:=+kmod-ppp
-  KCONFIG:= \
-	CONFIG_ISDN=y \
-    CONFIG_ISDN_I4L \
-    CONFIG_ISDN_PPP=y \
-    CONFIG_ISDN_PPP_VJ=y \
-    CONFIG_ISDN_MPP=y \
-    CONFIG_IPPP_FILTER=y \
-    CONFIG_ISDN_PPP_BSDCOMP \
-    CONFIG_ISDN_CAPI_MIDDLEWARE=y \
-    CONFIG_ISDN_CAPI_CAPIFS_BOOL=y \
-    CONFIG_ISDN_AUDIO=y \
-    CONFIG_ISDN_TTY_FAX=y \
-    CONFIG_ISDN_X25=y \
-    CONFIG_ISDN_DIVERSION
-  FILES:= \
-    $(LINUX_DIR)/drivers/isdn/divert/dss1_divert.ko \
-	$(LINUX_DIR)/drivers/isdn/i4l/isdn.ko \
-	$(LINUX_DIR)/drivers/isdn/i4l/isdn_bsdcomp.ko
-  AUTOLOAD:=$(call AutoLoad,40,isdn isdn_bsdcomp dss1_divert)
-endef
-
-define KernelPackage/isdn4linux/description
-  This driver allows you to use an ISDN adapter for networking
-endef
-
-$(eval $(call KernelPackage,isdn4linux))
-
-
 define KernelPackage/ipip
   SUBMENU:=$(NETWORK_SUPPORT_MENU)
   TITLE:=IP-in-IP encapsulation