net/liferea: Update to 1.14.6
- Add LGPL3 to the list of licenses
- Define LICENSE_FILE(s)
- Remove unneeded GNU_CONFIGURE_MANPREFIX
- Apply upstream patch to fix build with libxml2 2.12.0+
ChangeLog: https://github.com/lwindolf/liferea/releases/tag/v1.14.6
PR: 280329
Approved by: maintainer timeout >5 months