Support other fine tuned flux models and gguf versions

[KintCark]

Please add support for fine tuned flux models I'm trying to use chromav31unlocked.gguf but it's not working

[stduhpf]

Chroma is not just a fine tune, it's a pruned model with a slightly different block architecture.

All non-pruned Flux fine-tunes are supported, as well as pruned models that keep the same block architecture like Flex-1.