tracing: Fix comments about tracefs

There were some typos and mistakes in the tracefs code and the code
that calls tracefs.

Link: http://lkml.kernel.org/r/20150209055619.GA30788@sejong

Reported-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2 files changed