Apply recent changes done by Christos Zoulas <christos@zoulas.com>.
http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/sys/sys/queue.h?rev=1.70
* Revision 1.69, Mon Nov 2 14:49:07 2015 UTC by christos:
Use existing macros to implement TAILQ_FOREACH_REVERSE, like
TAILQ_FOREACH_REVERSE_SAFE does.
* Revision 1.70, Mon Nov 2 15:21:23 2015 UTC by christos:
Add missing paren.