The value of displayName is needed by later steps:
* When determining the IP address of the build VM
* When exporting the VM using ovftool
By default Packer will configure the VMX so `displayName` is equal to
the value defined for `vm_name` in the build template. However, it is
possible (and sometimes desirable) to set a custom value for
`displayName`.
Users can set a custom `displayName` through use of the `vmx_data`
option in their template.
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