libxl: introduce vNUMA types

libxl: introduce vNUMA types

A domain can contain several virtual NUMA nodes, hence we introduce an
array in libxl_domain_build_info.

libxl_vnode_info contains the size of memory in that node, the distance
from that node to every nodes, the underlying pnode and a bitmap of
vcpus.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Elena Ufimtseva <ufimtseva@gmail.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>