multimedia/audacious-plugins: Fix build after QT 6 upgrade
PR: 279322
Obtained from: https://github.com/audacious-media-player/audacious-plugins/commit/1f0bc4c6940d27905d11e3324e30c6a63fad6392
(cherry picked from commit 6418be43703e4b29116314888652ec752247cb49)