libbarrelfish: pmap serialisation: global mapping cnodes: allocate mapping cnodes in deserialise()  when GLOBAL_MCN is set
@@ -165,7 +165,7 @@ static errval_t deserialise_tree(struct pmap *pmap, struct serial_entry **in,
pmapx->used_cap_slots ++;
*/
-#if 0
+#if GLOBAL_MCN
/* allocate mapping cnodes */
for (int i = 0; i < MCN_COUNT; i++) {
err = cnode_create_l2(&n->u.vnode.mcn[i], &n->u.vnode.mcnode[i]);
