www/lighttpd: add missing annotated config file

Per the documentation of lighttpd 1.4.77, "Behavior Changes":
"doc/config/lighttpd.conf has been renamed doc/config/lighttpd.annotated.conf
and doc/config/lighttpd.conf is now a simpler header which includes
lighttpd.annotated.conf. lighttpd package maintainers must review their
packaging scripts and include both lighttpd.conf and lighttpd.annotated.conf
(e.g. doc/config/.conf) along with doc/config/conf.d/.conf."

PR: 285008