BC upgrader for dynamic Linear with torchbind (#38333)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/38333
Test Plan:
Imported from OSS
```
manifold get fblearner_inference_platform_models/tree/149745959/1/149745959_1.000 /tmp/149745959_1
```
In python:
```
import torch
torch.jit.load('/tmp/149745959_1')
```
` buck test mode/dev-nosan //caffe2/torch/fb/predictor/model_repo/tests:model_loading_test` passes
Reviewed By: ailzhang
Differential Revision: D21527444
Pulled By: jamesr66a
fbshipit-source-id: b33cab29df2d68beb482a044e604e41683e4fef6
