* feat: add Hygon DCU/DTK and Iluvatar CoreX platform support
Add build system and runtime support for two CUDA-compatible domestic
accelerator platforms:
- Hygon DCU with DTK SDK (USE_HYGON, /opt/dtk/cuda/cuda-11/)
- Iluvatar CoreX SDK (USE_COREX, /usr/local/corex/)
Both platforms expose CUDA-compatible APIs, so the integration follows
the same pattern as existing CUDA-like platforms (MUSA, MACA): add the
new macros to all platform guard chains and register SDK paths in CMake.
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Co-authored-by: KarmaD7 <KarmaD7@users.noreply.github.com>