libtraceevent: Only add space on log prints if perror is used

Do not add the space is the perror is not printed, as the space was only
to separate the perror output from the rest of the output.

Link: https://lore.kernel.org/linux-trace-devel/20220216031345.984113-2-rostedt@goodmis.org

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
1 file changed