Place the data structures that are required for constructing a VmConfig
into it's own module from the logic that exists to suppot them.
This is useful as a consumer of the API can now clearly see what data
structures make up the API for creating VMs.
This has no functional change and I made no attempt to clean up the
ordering (it's as in the original file) nor any other clean up.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>