tipc: Prevent display of name table types with no publications

This patch adds a check to prevent TIPC's name table display code
from listing a name type entry if it exists only to hold subscription
info, rather than published names.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/name_table.c

@@ -905,6 +905,9 @@ static void nameseq_list(struct name_seq *seq, struct print_buf *buf, u32 depth,
 	struct sub_seq *sseq;
 	char typearea[11];
 
+	if (seq->first_free == 0)
+		return;
+
 	sprintf(typearea, "%-10u", seq->type);
 
 	if (depth == 1) {