libtracefs: Add documentation for tracefs_option_id()

The function tracefs_option_id() is missing from the man pages.

Add it.

Link: https://lore.kernel.org/linux-trace-devel/20220223003012.1334741-9-rostedt@goodmis.org

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