Fix bugs in llm-relay overwriting ops + repeating file names

[PaliC]

Overwriting Ops

Currently llm-relay defines it's backend as a dictionary of { op_name: compiled_kernel }. Unfortunately, from the way it grabs the op_name multiple distinct ops can have the same name (an example is aten.div.Tensor_mode which is the name of two seperate ops).

• Investigate the differences between these ops
• If separate kernels are warranted, ensure that llm-relay actually writes separate kernels for these, otherwise, have llm-relay generate a single kernel for the set of ops and reflect that in the reporting.

Overwriting Files

A bigger issue is that we are overwriting files when there is a different overload. For example with div we have 2 separate overloads, but only the result for aten.div.Tensor_mode shows up. Fortunately, this is an easy solve.

• When Centralize operator canonicalization  #124 is merged use the actual operator name for the folder (or whatever directory_backend is using)

[msaroufim]

I suspect if we're collapsing multiple ops into the same folder then we also need to collapse multiple tests for ops in the same family into a single test. Granted let's see how my other PR goes before deciding anything here