pmem_lpg_concat
static void pmem_lpg_concat(pmem_lpg_t **, pmem_lpg_t **);
pmem_lpg_concat(&pmem_occ_lpgs, &plp);
pmem_lpg_concat(&pf_lpgs, &plp);
pmem_lpg_concat(&pmem_occ_lpgs, &pf_lpgs);
pmem_lpg_concat(plpp, &plp);