tracing: Improve message of empty set_graph_notrace file

When there's no entry in set_graph_notrace, it'll print below message

  #### all functions enabled ####

While this is technically correct, it's better to print like below:

  #### no functions disabled ####

Link: http://lkml.kernel.org/p/1402590233-22321-3-git-send-email-namhyung@kernel.orgReported-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: NNamhyung Kim <namhyung@kernel.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

kernel/trace/ftrace.c

@@ -4089,7 +4089,12 @@ static int g_show(struct seq_file *m, void *v)
 		return 0;
 
 	if (ptr == (unsigned long *)1) {
+		struct ftrace_graph_data *fgd = m->private;
+
+		if (fgd->table == ftrace_graph_funcs)
 			seq_printf(m, "#### all functions enabled ####\n");
+		else
+			seq_printf(m, "#### no functions disabled ####\n");
 		return 0;
 	}