[Inductor] Use indices for constants in triton_meta (#121427)
@bertmaher pointed out that constants are passed with their indices, not their names. Looking at triton source, this appears to be true https://github.com/openai/triton/blob/392370b3030884ea4179e4b139f890b9a0db0361/python/triton/runtime/jit.py#L381-L385
I'm guessing both indices and names work here but lets be consistent.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/121427
Approved by: https://github.com/aakhundov
