netfilter: nf_log: add module softdeps

xt_LOG has no direct dependency on the syslog-based logger, it relies
on the nf_log core to probe the requested backend.

Now that all syslog-based loggers reside in the same module, we can
just add a soft dependency on nf_log_syslog and let modprobe take
care of it.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/xt_LOG.c

@@ -108,3 +108,4 @@ MODULE_AUTHOR("Jan Rekorajski <baggins@pld.org.pl>");
 MODULE_DESCRIPTION("Xtables: IPv4/IPv6 packet logging");
 MODULE_ALIAS("ipt_LOG");
 MODULE_ALIAS("ip6t_LOG");
+MODULE_SOFTDEP("pre: nf_log_syslog");

net/netfilter/xt_NFLOG.c

@@ -79,3 +79,4 @@ static void __exit nflog_tg_exit(void)
 
 module_init(nflog_tg_init);
 module_exit(nflog_tg_exit);
+MODULE_SOFTDEP("pre: nfnetlink_log");

net/netfilter/xt_TRACE.c

@@ -52,3 +52,4 @@ static void __exit trace_tg_exit(void)
 
 module_init(trace_tg_init);
 module_exit(trace_tg_exit);
+MODULE_SOFTDEP("pre: nf_log_syslog");