Hello guix

This is a patch that allows acl to be built when hurd is targeted.

Is it okay to push to wip-hurd?

I have rebased wip-hurd on top of master locally and I have removed
some things from commit ea44aa1b33933328aa0b7b33f36dfcc90aaa8c74
that were no longer needed.
I will resend that patch for review before I push. All the others are the same.


Manolis