Remove double soft-max in load-balancing loss. Fixes #39055 .
Author: rudolfwilliam
Pull request: yes

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Fixes #39055 


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Comments:
I went trough some other classes (but not all) that use the same load balancer, like qwen moe and jetmoe. It seems they implement load balancing correctly (they either operate explicitly on the probabilities-as implemented in my pull request- or correctly pass logits to the function).

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