package/libtraceevent: bump to version 1.8.7
Release notes:
https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/tag/?h=libtraceevent-1.8.7
Signed-off-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>