Add missing WWW entries
These ports reference the pkg-descr file of some other port and used
to get the WWW entry from that other port's file.
Reported by: dan@langille.org (Dan Langille)
Update to CentOS 7.7.1908.
Put libdrm into a separate port so it can be kept at the CentOS 7.6 version.
The new version fails to detect graphics hardware on FreeBSD.