Add ONNX export support for DinoV2, Hiera, Maskformer, PVT, SigLIP, SwinV2, VitMAE, and VitMSN models

[xenova]

What does this PR do?

Fixes # (issue)

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[SangbumChoi]

@xenova Hi xenova! I think you missed to add official support for maskformer

optimum/optimum/onnxruntime/modeling_ort.py

Line 1773 in de07c7a

ONNX Model for semantic-segmentation, with an all-MLP decode head on top e.g. for ADE20k, CityScapes. This class officially supports segformer.