scriplet issues installing deps in f23 mock

[Miroslav Suchý]

Tracked under:
https://bugzilla.redhat.com/show_bug.cgi?id=1268883

What we know so far is:
 * it happen under F23
 * it works in F22
 * it works with dnf
 * it does not work with yum.

So "mock --dnf" can be used as temporary workaround for those who are blocked by this.

-- 
Miroslav Suchy, RHCA
Red Hat, Senior Software Engineer, #brno, #devexp, #fedora-buildsys