selftests/ftrace: Add test case for GRP/ only input

Add kprobe and eprobe event test for new GRP/ only format.

Link: https://lore.kernel.org/all/1656296348-16111-5-git-send-email-quic_linyyuan@quicinc.com/



Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>