remove to restriction for 4-bit model (#33122)
* remove to restiction for 4-bit model
* Update src/transformers/modeling_utils.py
Co-authored-by: Matthew Douglas <38992547+matthewdouglas@users.noreply.github.com>
* bitsandbytes: prevent dtype casting while allowing device movement with .to or .cuda
* quality fix
* Improve warning message for .to() and .cuda() on bnb quantized models
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Co-authored-by: Matthew Douglas <38992547+matthewdouglas@users.noreply.github.com>
