ftrace: fix documentation typo s/trace_max_latency/tracing_max_latency/

There isn't a trace_max_latency file, there is tracing_max_latency.
Fix it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
LKML-Reference: <20090307235409.5A87.A69D9226@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/Documentation/ftrace.txt b/Documentation/ftrace.txt
index 22614be..fd9a3e6 100644
--- a/Documentation/ftrace.txt
+++ b/Documentation/ftrace.txt
@@ -100,7 +100,7 @@
 	that is displayed in one of the above output
 	files.
 
-  trace_max_latency:
+  tracing_max_latency:
 
 	Some of the tracers record the max latency.
 	For example, the time interrupts are disabled.