x11/lxqt-about: add missing translation files

> Checking for items in STAGEDIR missing from pkg-plist

Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_arn.qm
Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_ast.qm
Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_bg.qm
Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_fa.qm
Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_pt_PT.qm
Error: Orphaned: %%LXQT_TRANSLATIONS%%/lxqt-about/lxqt-about_sv.qm

Approved by: fixit-blanket