[inf] Add config var to enable keeping module on host (#6846)
Using keep_module_on_host config var will let us control if the loaded
checkpoints to model parameters will be moved to the device or stay on
host
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Co-authored-by: Olatunji Ruwase <olruwase@microsoft.com>
Co-authored-by: Logan Adams <114770087+loadams@users.noreply.github.com>
