[BugFix]: Add missing clamp to llavavid

[PanJason]

Motivation

Add clamp to llavavid model so that the placeholder for video input won't casue out-of-bound error when running LLaVA-NeXT-Video-7B using srt_example_llava_v.py. The error is shown below.

Modifications

Add input_ids.clamp to model forward

Checklist

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