test: ftrace: Fix kprobe test for eventfs

kprobe_args_char.tc, kprobe_args_string.tc has validation check
for tracefs_create_dir, for eventfs it should be eventfs_create_dir.

Link: https://lkml.kernel.org/r/1690568452-46553-11-git-send-email-akaher@vmware.com



Signed-off-by: Ajay Kaher <akaher@vmware.com>
Co-developed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Ching-lin Yu <chinglinyu@google.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>