Returns the hard disk size.
PRL_RESULT PrlVmDevHd_GetDiskSize( PRL_HANDLE hVmDev, PRL_UINT32_PTR pnDiskSize );
PrlApiVm.h
PRL_RESULT. Possible values:
PRL_ERR_INVALID_ARG - invalid handle or null pointer was passed.
PRL_ERR_SUCCESS - function completed successfully.