Revert "Setup mdadm to turn off homehost (#1156614)"
This reverts commit 0bcbab3c718d5acf52315c11aa3e42d6b5d01368.
Per https://bugzilla.redhat.com/show_bug.cgi?id=1156614#c15 both
dlehman and I suspect it may be completely wrong, and it's not
strictly necessary right now, so let's leave it until dledford
clarifies.