[inductor] Clean up TRITON_CACHE_DIR (#92879)
Summary:
As a follow up in https://github.com/pytorch/pytorch/pull/92664 (D42619405 (https://github.com/pytorch/pytorch/commit/e6a8267cf54af30e33de1ef22625e972afbf03ff)), clean up the TRITON_CACHE_DIR settings. There are a few places touching TRITON_CACHE_DIR:
1. triton/fb/triton_util.py: when import triton
2. caffe2/torch/_inductor/codecache.py
3. caffe2/torch/_inductor/triton_ops/autotune.py
4. triton/triton/python/triton/compiler.py
IIUC there are two entry points:
* kernel.run(args): 1 -> 3 -> 4
* async_compile(kernel): 1 -> 2 -> 3 -> 4
* calling triton jit-annoated func directly: 4
I'm removing the TRITON_CACHE_DIR in 1 and 2.
Test Plan: Run local repro
Differential Revision: D42694374
Pull Request resolved: https://github.com/pytorch/pytorch/pull/92879
Approved by: https://github.com/jansel
