hammer2_freemap_alloc
int hammer2_freemap_alloc(hammer2_chain_t *chain, size_t bytes);
error = hammer2_freemap_alloc(chain, nbytes);
error = hammer2_freemap_alloc(chain,
int hammer2_freemap_alloc(hammer2_chain_t *chain, size_t bytes);
error = hammer2_freemap_alloc(chain, nbytes);
error = hammer2_freemap_alloc(chain,