libtracefs: Add check for duplicate functions in man pages

Update the check-manpages.sh script to make sure that there are no
functions that are described in more than one man page.

Link: https://lore.kernel.org/linux-trace-devel/20230104172655.145516-2-rostedt@goodmis.org/
Link: https://lore.kernel.org/linux-trace-devel/20230104123100.63349d71@gandalf.local.home

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