FP8 support for tokamax gmm kernel

[khatwanimohit]

Description

This PR calls tokamax_api.gmm in megablox/ops.py for supporting FP8 quantization using tokamax's gmm kernel. It also extends the tiling configs to 18 values, 9 for wi-* and 9 for wo tensors.

If the change fixes a bug or a Github issue, please include a link, e.g.,:
FIXES: b/458461066

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Tests

Command to repro: https://paste.googleplex.com/6669707558125568
Xprof: http://shortn/_HoU0Xj2IZ9

Checklist

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[github-actions]

🤖 Hi @RissyRan, I've received your request, and I'm working on it now! You can track my progress in the logs for more details.

[github-actions]

📋 Review Summary

This pull request adds support for FP8 quantization using the tokamax GMM kernel. The changes are well-structured and introduce fine-grained configuration for tiling dimensions. The core logic is updated to switch between the existing megablox backend and the new tokamax backend.

🔍 General Feedback

• The introduction of specific tiling configurations for forward and backward passes is a good improvement for tunability.
• The changes in moe.py to support the tokamax backend are well-integrated.
• I've left a few minor suggestions for improving code clarity and fixing a potential typo. There is also a question about a change in implementation detail that might affect performance.

[RissyRan]

LGTM! Just one comment to move proper assertion in moe.py to the pyconfig file