OptimizedLinear implementation (#5355)
Optimized version of `nn.Linear` that adds features such as:
* LoRA w. base weight sharding
* FP [6,8,12] quantization
Depends on #5336 being merged first
Co-authored-by: @rajhans
Co-authored-by: @aurickq
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Co-authored-by: Rajhans Samdani <rajhans.samdani@snowflake.com>
Co-authored-by: Jeff Rasley <jeff.rasley@snowflake.com>
