Commitment and Commitment State for Linear Code PCS are private

## Summary of Bug

The data structures of poly-commit/src/linear_codes have restricted visibility. Specifically, the LinCodePCCommitment and LinCodePCCommitmentState data structures required to store the commitments are currently private.

## Version

0.5.0

## Steps to Reproduce

https://github.com/arkworks-rs/poly-commit/blob/a05ec99d0d3e46c8ba0d6d3592980777bc2847e8/poly-commit/src/linear_codes/mod.rs#L37C9-L37C24

We could just change it to
```
pub use data_structures::*;
```

if not to
```
pub use data_structures::{
BrakedownPCParams, LigeroPCParams,
LinCodePCProof, LinCodePCCommitment,
LinCodePCCommitmentState
};
```