Problem: build fails with GCC 7

Solution: fix truncation

Author: bluca

src/fmq_client_engine.inc

@@ -196,7 +196,7 @@ s_client_new (zsock_t *cmdpipe, zsock_t *msgpipe)
         self->msgpipe = msgpipe;
         self->state = start_state;
         self->event = NULL_event;
-        snprintf (self->log_prefix, sizeof (self->log_prefix) - 1,
+        snprintf (self->log_prefix, sizeof (self->log_prefix),
             "%6d:%-33s", randof (1000000), "fmq_client");
         self->dealer = zsock_new (ZMQ_DEALER);
         if (self->dealer)

src/fmq_server_engine.inc

@@ -270,7 +270,7 @@ engine_set_log_prefix (client_t *client, const char *string)
 {
     if (client) {
         s_client_t *self = (s_client_t *) client;
-        snprintf (self->log_prefix, sizeof (self->log_prefix) - 1,
+        snprintf (self->log_prefix, sizeof (self->log_prefix),
             "%6d:%-33s", self->unique_id, string);
     }
 }