kernel: fix missing dependency in 4.14.108

The 4.14.108 bump introduced a missing dependency when building
specific netfilters.

Thsi was not seen as the error does not occur on all targets.

Thanks to Jo-Philipp Wich for providing the fix

Fixes: af6c86dbe5 ("kernel: bump 4.14 to 4.14.108")
Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>

package/kernel/linux/modules/netfilter.mk

@@ -368,7 +368,7 @@ IPVS_MODULES:= \
 define KernelPackage/nf-ipvs
   SUBMENU:=Netfilter Extensions
   TITLE:=IP Virtual Server modules
-  DEPENDS:=@IPV6 +kmod-lib-crc32c +kmod-ipt-conntrack +kmod-nf-conntrack
+  DEPENDS:=@IPV6 +kmod-lib-crc32c +kmod-ipt-conntrack +kmod-nf-conntrack +LINUX_4_14:kmod-nf-conntrack6
   KCONFIG:= \
 	CONFIG_IP_VS \
 	CONFIG_IP_VS_IPV6=y \