selftests/ftrace: Fix eprobe syntax test case to check filter support

selftests/ftrace: Fix eprobe syntax test case to check filter support

commit d07c89c90fd92ef4b1fa91254637b9f0134b0006 upstream.

Fix eprobe syntax test case to check whether the kernel supports the filter
on eprobe for filter syntax test command. Without this fix, this test case
will fail if the kernel supports eprobe but doesn't support the filter on
eprobe.

Link: https://lore.kernel.org/all/167309834742.640500.379128668288448035.stgit@devnote3/
Fixes: e82c95efa116 ("selftests/ftrace: Add eprobe syntax error testcase")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>