trace-events: Shorten file names in comments

trace-events: Shorten file names in comments

We spell out sub/dir/ in sub/dir/trace-events' comments pointing to
source files.  That's because when trace-events got split up, the
comments were moved verbatim.

Delete the sub/dir/ part from these comments.  Gets rid of several
misspellings.

Signed-off-by: Markus Armbruster <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Message-id: 20190314180929[email protected]
Message-Id: <20190314180929[email protected]>
Signed-off-by: Stefan Hajnoczi <[email protected]>