Adding support for wav2vec2 large models.

[kauterry]

What does this PR do? Please describe:
Adds support for wav2vec2 large models trained on Librispeech 960h (ls960) and LibriVox 60k (lv60k).

Tested with this simple code snippet:
lv60k

from fairseq2.models.wav2vec2.setup import load_wav2vec2_model
import torch

model = load_wav2vec2_model("wav2vec2_large_lv60k", device=torch.device("cuda:0"), dtype=torch.float32)
print(model)

Output: P1230849615

ls960:

from fairseq2.models.wav2vec2.setup import load_wav2vec2_model
import torch

model = load_wav2vec2_model("wav2vec2_large_ls960", device=torch.device("cuda:0"), dtype=torch.float32)
print(model)

Output: P1230849916

Fixes #{issue number}

Does your PR introduce any breaking changes? If yes, please list them:
List of all backwards-incompatible changes.

Check list:

• Was the content of this PR discussed and approved via a GitHub issue? (no need for typos or documentation improvements)
• Did you read the contributor guideline?
• Did you make sure that your PR does only one thing instead of bundling different changes together?
• Did you make sure to update the documentation with your changes? (if necessary)
• Did you write any new necessary tests?
• Did you verify new and existing tests pass locally with your changes?
• Did you update the CHANGELOG? (no need for typos, documentation, or minor internal changes)

[cbalioglu]

Thanks a lot for the new configs! Just left two nit comments.

[cbalioglu]

Just left a few nit comments about naming. Otherwise, looks good. Once you address them, we can merge it.

[cbalioglu]

LGTM! Thanks for the contribution! :)