[PyTorch] Expose bias() and unpack() API of LinearPackedParamsBase to Python layer (#61855)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/61855
Exposing `bias()` and `unpack()` for `LinearPackedParamsBase`. This is useful for inspecting linear op attributes.
Test Plan:
See unit test passing:
```
[ (6c61a5eb4) | devvm1625 ~/fbsource/fbcode] buck test //caffe2/test:quantization -- test_linear_bias_unpack
Parsing buck files: finished in 2.8 sec
Building: finished in 9.9 sec (100%) 11973/55220 jobs, 0/55220 updated
Total time: 12.8 sec
More details at https://www.internalfb.com/intern/buck/build/2d0ee210-c8f3-4994-ac2b-1dccf4c3ca6c
Tpx test run coordinator for Facebook. See https://fburl.com/tpx for details.
Running with tpx session id: b7c6ea1b-8eef-430e-b83a-dad4033ecc87
Trace available for this run at /tmp/tpx-20210720-115423.031745/trace.log
Started reporting to test run: https://www.internalfb.com/intern/testinfra/testrun/5348024618459562
✓ ListingSuccess: caffe2/test:quantization - main (10.806)
✓ Pass: caffe2/test:quantization - test_linear_bias_unpack (quantization.core.test_quantized_op.TestQuantizedOps) (10.913)
Summary
Pass: 1
ListingSuccess: 1
If you need help understanding your runs, please follow the wiki: https://fburl.com/posting_in_tpx_users
Finished test run: https://www.internalfb.com/intern/testinfra/testrun/5348024618459562
```
Reviewed By: kimishpatel
Differential Revision: D29767704
fbshipit-source-id: 716f43b61814b92094c0b08d4e63e1dddc352aa7
