[Bugfix]Disable the post_norm layer of the vision encoder for LLaVA models

[litianjian]

Disable the post_norm layer of vision encoder for LLaVA-Onevision models based on #9217.

[github-actions]

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[DarkLight1337]

Does this issue occur for the other LLaVA models as well?

[litianjian]

Does this issue occur for the other LLaVA models as well?

Other LLaVA models can still use num_hidden_layers_override to determine whether enable post_layer_norm layer. However, I believe that consistently using this parameter for judgment would be better.

[DarkLight1337]

Let's update the other models then, since from a quick look at the HF implementation, they don't use post_layernorm.

[litianjian]

Let's update the other models then, since from a quick look at the HF implementation, they don't use post_layernorm.

OK, all LLaVA models don't use post_layernorm.

[DarkLight1337]

Thanks for fixing!