dns_HINFO_reply event was never being generated.

On top of that, I modified the event to pass the relevant fields from the DNS message.

testing/btest/scripts/base/protocols/dns/hinfo.zeek

@@ -0,0 +1,9 @@
+# @TEST-EXEC: zeek -b -r $TRACES/dns/hinfo.pcap %INPUT
+# @TEST-EXEC: btest-diff .stdout
+
+@load base/protocols/dns
+
+event dns_HINFO_reply(c: connection, msg: dns_msg, ans: dns_answer, cpu: string, os: string)
+	{
+	print "HINFO", msg, ans, cpu, os;
+	}