Unbreak no-ip and no-inet6 module builds with ipfw. For now continue to build the ip_fw_pfil.c hooks and ipfw even in case of no-ip under the assumption that the private L2 hook (which hopefully eventually will be a pfil hook as well) can still be useful. Allow building the module without inet as well. Glanced at by: jhb MFC after: 3 days
head/sys/modules/ipfw/Makefile
head/sys/netinet/ipfw/ip_fw_pfil.c