This fixes an issue, when a host group was passed to mq_setup role,
and delegate logic uses group name instead of host inside of the
group for delegating tasks.
While this patch might break already in-place workarounds, it's
quite important to fix the issue properly, as workarounds are not
trivial and requires quite some understanding of the process.
Closes-Bug: #2111406
Change-Id: Ic5747e29050cced51a71a4b4e71352f231758ed8
46862920df