The counters for the traceon and traceoff are only suppose to decrement
when the trigger enables or disables tracing. It is not suppose to decrement
every time the event is hit.

Only decrement the counter if the trigger actually did something.

Link: http://lkml.kernel.org/r/20140106223124.0e5fd0b4@gandalf.local.homeAcked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>