sysutils/superfile: update to v1.6.1-0.20260618150422-5845124b77cd

This is basically 1.6.0 plus a fix to add a missing dependency to
go.mod (otherwise I'd have to mess with USE_GITHUB) and a patch to
port extended attribute support to FreeBSD.

Changelog: https://github.com/yorukot/superfile/releases/tag/v1.6.0