Mention NVIDIA non-commercial in top LICENSE section

[junkoda]

Could you mention NVIDIA license, which is written in encoders/mix_transformer.py, in the top LICENSE section?

This can cause a problem for commercial use including Kaggle, in which the competition rule often requires commercial use. I misunderstood that segFormer had become completely MIT.

For example, mmcv has a LICENSES page, which lists files with NVIDIA license.
https://github.com/open-mmlab/mmcv/blob/main/LICENSES.md

Thanks for developing and maintaining this great library! I am using a lot for Kaggle.

[qubvel]

Hi @junkoda! Thanks for opening issue! Sure, that's should be listed, would you like to make a PR?

[junkoda]

Okay! That's an unfamiliar task, but I'll try in the next couple of days.

[qubvel]

Thanks! I would appreciate your contribution!