cgroup: always recreate cgroup before we try to apply attributes

We might have trimmed the cgroup tree previously, hence don't trust our
own "realized" flag, always recreate cgroup tree before applying our
attributes to make sure this actually works out.

https://bugzilla.redhat.com/show_bug.cgi?id=749687

src/cgroup.c

@@ -38,9 +38,6 @@ int cgroup_bonding_realize(CGroupBonding *b) {
         assert(b->path);
         assert(b->controller);
 
-        if (b->realized)
-                return 0;
-
         r = cg_create(b->controller, b->path);
         if (r < 0) {
                 log_warning("Failed to create cgroup %s:%s: %s", b->controller, b->path, strerror(-r));