Now that event_create_dir() and __trace_add_new_event() always
use the same file_operations we can kill these arguments and
simplify the code.

Link: http://lkml.kernel.org/r/20130731173135.GA31040@redhat.comSigned-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>