ftrace: Calculate the correct dyn_ftrace number to report to the userspace

Now, ftrace only calculate the dyn_ftrace number in the adding
breakpoint loop, not in adding update and finish update loop.

Calculate the correct dyn_ftrace, once ftrace reports the failure message
to the userspace.

Link: http://lkml.kernel.org/r/1442420382-13130-1-git-send-email-mnfhuang@gmail.com



Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>