Add support for scalar FP8 weight scales (#2550)
* Add support for scalar FP8 weight scales
* Support LLM compressor FP8 checkpoints on H100
On H100, we use fbgemm-gpu, which requires bfloat16 as the input dtype.
However, we wouldn't pick up fp8 quantization for models quantized with
LLM compressor. This change adds enough parsing to detect if models have
FP8-quantized weights.
* Remove stray debug print