[inductor] Make autotune_process.py pass mypy (#105791)
`TensorMeta.from_irnodes` handles either a single `IRNode` or a tuple or list of them. I tried to express this with overloading, but because this file is in MYPYNOFOLLOW, the `IRNode` subclasses become `Any`, which causes the overloads to be overlapping.
This changes the type of the argument to `benchmark_in_sub_process` to the more specific `TritonTemplateCaller`, since that one has the `bmreq` member and existing docstrings indicate that only the triton template benchmark is handled.
The `rand_strided` call caused a mypy error because the default value for device was a string. This is fixed by adding type hints to `rand_strided` in `torch/_dynamo/testing.py`. Likewise, the return value of `PyCodeCache.load_by_key_path` can be inferred from the type hint on `PyCodeCache.cache`.
Fixes one part of #105230
Pull Request resolved: https://github.com/pytorch/pytorch/pull/105791
Approved by: https://github.com/jansel, https://github.com/Skylion007
