fix: gate Moore MCCL bfloat16 support by MARCH_TYPE

[Ziminli]

Summary

This PR fixes Moore MCCL BF16 dtype mapping so Moore builds only advertise DataType::kBFloat16 when the target architecture supports it. The change replaces the previous global build-definition approach with device-specific MCCL datatype traits, while keeping MetaX BF16 support unchanged.

Changes

• Device-specific MCCL dtype traits
  • Added McclDataTypeTraits<device> specializations for MetaX and Moore;
  • MetaX maps BF16 to mcclBfloat16; Moore maps BF16 to mcclBfloat16 only for MARCH_TYPE >= 220, otherwise mcclNumTypes.
• MCCL type map
  • Made McclDataTypeMap and DataTypeToMcclType() device-templated so CclTypeMap<BackendType::kMccl, device> resolves BF16 per device.
• Build cleanup
  • Removed INFINI_CCL_MCCL_BFLOAT16_UNSUPPORTED compile definitions from library and example targets because support is now selected by the trait.

Platform and Backend Affected

Platform

• CPU
• NVIDIA GPU
• Iluvatar GPU
• MetaX GPU
• Moore Threads GPU
• Cambricon MLU

Backend

• OpenMPI
• MPICH
• NCCL
• MCCL

Performance Impact

• No performance impact
• Performance improved
• Performance regression possible

N/A.

Known Issues & Future Work

N/A.

Test Results

Test Involved Platform

• CPU
• NVIDIA GPU
• Iluvatar GPU
• MetaX GPU
• Moore Threads GPU
• Cambricon MLU

Test Involved Backend

• OpenMPI
• MPICH
• NCCL
• MCCL

Moore (MCCL, OpenMPI):
moore_ccl_mpi_hybrid_all_reduce.log
moore_ccl_all_reduce.log

MetaX (MCCL, OpenMPI):
metax_ccl_all_reduce.log
metax_ccl_mpi_hybrid_all_reduce.log

Moore + MetaX (OpenMPI):
mpi_all_gather.log
mpi_all_reduce.log
mpi_all_to_all.log
mpi_broadcast.log
mpi_gather.log
mpi_reduce.log
mpi_reduce_scatter.log
mpi_scatter.log
mpi_send_recv.log

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Checklist

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Scope and Design

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General Code Hygiene

• The code is self-explanatory; comments were added only where the intent or rationale is non-obvious (CONTRIBUTING.md §Code/General).
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C++ Specific (if C++ files changed)

• Code follows the Google C++ Style Guide strictly.
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Python Specific (if Python files changed)

• N/A - No Python files changed.

Testing

• All applicable example programs have been built and tested successfully on at least one supported heterogeneous cluster setup.

Build, CI, and Tooling

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Documentation

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Security and Safety

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