Direction for extending MXGemmKernelChoice/MXLinearRecipeName for XPU support

[slabhs-aws]

Hi team,

TorchAO today provides 3 MXGemm kernel paths:

EMULATED
CUTLASS
CUBLAS

For users running MX workloads on XPUs, it’s unclear how future MX kernel selection is intended to evolve.

Questions:

1. Should XPU-based execution map into MXGemmKernelChoice, or is there a different path to onboard new XPU architectures?
2. Similarly, how do we scale MXLinearRecipeName

This context affects how upstream frameworks (e.g., torchtitan) gate MX execution.

Cross-referencing with the related torchtitan discussion: pytorch/torchtitan#2120

Thank you!