`enable_cache_file_io_in_mem` makes Vitis incapable of using NPU

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Using official gte-large-en-v1.5-bf16 example (which is, by the way, broken without some serious effort to run it) reveals that Vitis, when enable_cache_file_io_in_mem is disabled (set to 0) Vitis tries to write file cache onto the disk and does so successfully but potentially when trying to validate/load/use it (it's proprietary right?) fails to do so, fails silently, and falls back to CPU. And by "silent" I mean, it leaves user wondering what is going on, it is completely implicit even if this is overall intended/expected.