domain per-NUMA node memory allocation.

If vnuma topology is defined and running on hardware NUMA machine,
allocate vnodes on physical numa nodes based on vnode_to_pnode map.

Changes since v1:
- fixed incorrect output of number of pages per vnode for domain
in case of a failure.
- fixed returned error codes.

Signed-off-by: Elena Ufimtseva <ufimtseva@gmail.com>