[AI Bench] Resumme speed_benchmark_torch.cc to origin
Summary: we removed all assistant specific code
Test Plan:
```
buck run aibench:run_bench -- -b aibench/specifications/models/pytorch/fbnet/fbnet_mobile_inference.json --platform android/full_jit --framework pytorch --remote --devices SM-G950U-7.0-24
```
https://our.intern.facebook.com/intern/aibench/details/940147322057842
Reviewed By: kimishpatel
Differential Revision: D20686220
fbshipit-source-id: b7336d5ea15fa11be01abf4ad12747feaaf22ea8
