[SYCL] Add macro to disable SYCL's device copyability checks (#23102)
This PR adds a new macro, **SYCL_DISABLE_DEVICE_COPYABLE_CHECKS**, that
makes `sycl::is_device_copyable_v<T>` report `true` for every type, and
disables all diagnostics that the SYCL headers issue when a type does
not satisfy the device copyability requirements of the SYCL
specification.
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Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>