app-admin/rsyslog: Restricting build depedencies for v8.16.0

app-admin/rsyslog: Restricting build depedencies for v8.16.0

While this version builds against =dev-libs/libfastjson-0.99.2 it does not
build against >dev-libs/libfastjson-0.99.2.

Additional, if you build rsyslog against dev-libs/json-c but build also against
dev-libs/liblognorm which was build against >dev-libs/libfastjson-0.99.2
you will get runtime errors.

To solve this problem we are restricting rsyslog-8.16.0 to build only against
dev-libs/json-c and also restricting to =dev-libs/liblognorm-1.1.2* (last
version which builds against dev-libs/json-c).

Package-Manager: portage-2.3.0