lxc: Fix access to hostdev capabilities

lxc: Fix access to hostdev capabilities

In a few places, where a capabilities <hostdev/> is processed, a
wrong union member is access: def->source.subsys.type instead of
def->source.caps.type. Fortunately, both union members have .type
as the very first member so no real harm is done. Nevertheless,
we should access the correct union member.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>