multimedia/libzen: Revert to previous commit

Last commit by maintainer broke users of mediainfo, revert related
libraries prior to this change
This retains changes to WWW and pkg-descr

PR: 268709, 269601
Reported by: Michiel van Baak Jansen <michiel@vanbaak.eu>
Approved by: portmgr (blanket, maintainer timeout: 3+ weeks)
Fixes: 23e0c77