fix for vllm #30623 and #27814

[gpolovets1]

Description

Updated imports to use reorganized FusedMoE paths made by vllm-project/vllm#30623.
Overrode initialization logic of fp8 linear layer to workaround refactor in vllm-project/vllm#27814.

Collaborators are kyuyeunk@, lk-chen@, JiriesKaileh@

Tests

Pre-submit build kite passes.

Checklist

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• I have performed a self-review of my code.
• I have necessary comments in my code, particularly in hard-to-understand areas.
• I have made or will make corresponding changes to any relevant documentation.

[github-actions]

Description

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FIXES: #123456

Tests

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Checklist

Before submitting this PR, please make sure:

• I have performed a self-review of my code.
• I have necessary comments in my code, particularly in hard-to-understand areas.
• I have made or will make corresponding changes to any relevant documentation.